Merge branch 'release/0.16'

CMakeLists.txt

@@ -28,9 +28,9 @@ enable_testing()
 
 message(STATUS "Using ${CMAKE_CXX_COMPILER} (compiler id: ${CMAKE_CXX_COMPILER_ID})")
 if ("${CMAKE_CXX_COMPILER_ID}" STREQUAL "Clang")
-	set(CMAKE_CXX_FLAGS "-std=c++11 -stdlib=libc++ ${CMAKE_CXX_FLAGS}")
+	set(CMAKE_CXX_FLAGS "-std=c++11 -stdlib=libc++ -Wall ${CMAKE_CXX_FLAGS}")
 elseif ("${CMAKE_CXX_COMPILER_ID}" STREQUAL "GNU")
-	set(CMAKE_CXX_FLAGS "-std=c++11 ${CMAKE_CXX_FLAGS}")
+	set(CMAKE_CXX_FLAGS "-std=c++11 -Wall ${CMAKE_CXX_FLAGS}")
 endif ()
 
 set(include_dir "${PROJECT_SOURCE_DIR}/include")

include/sqlpp11/alias.h

@@ -28,45 +28,39 @@
 #define SQLPP_ALIAS_H
 
 #include <sqlpp11/type_traits.h>
+#include <sqlpp11/serializer.h>
+
 namespace sqlpp
 {
 	template<typename Expression, typename AliasProvider>
 		struct expression_alias_t
 		{
+			using _traits = make_traits<value_type_of<Expression>, tag::named_expression, tag::alias>;
+			using _recursive_traits = make_recursive_traits<Expression>;
+
 			static_assert(is_expression_t<Expression>::value, "invalid argument for an expression alias");
 			static_assert(not is_alias_t<Expression>::value, "cannot create an alias of an alias");
 
-			struct _value_type: Expression::_value_type
-			{
-				using _is_expression = std::false_type;
-				using _is_named_expression = std::true_type;
-				using _is_alias = std::true_type;
-			};
-
 			using _name_t = typename AliasProvider::_name_t;
-			using _table_set = typename Expression::_table_set;
 
 			Expression _expression;
 		};
 
-	namespace vendor
-	{
-		template<typename Context, typename Expression, typename AliasProvider>
-			struct serializer_t<Context, expression_alias_t<Expression, AliasProvider>>
+	template<typename Context, typename Expression, typename AliasProvider>
+		struct serializer_t<Context, expression_alias_t<Expression, AliasProvider>>
+		{
+			using T = expression_alias_t<Expression, AliasProvider>;
+
+			static Context& _(const T& t, Context& context)
 			{
-				using T = expression_alias_t<Expression, AliasProvider>;
+				context << '(';
+				serialize(t._expression, context);
+				context << ") AS ";
+				context << T::_name_t::_get_name();
+				return context;
+			}
+		};
 
-				static Context& _(const T& t, Context& context)
-				{
-					context << '(';
-					serialize(t._expression, context);
-					context << ") AS ";
-					context << T::_name_t::_get_name();
-					return context;
-				}
-			};
-
-	}
 }
 
 #endif

include/sqlpp11/alias_provider.h

@@ -31,20 +31,20 @@
 
 #define SQLPP_ALIAS_PROVIDER(name) \
 	struct name##_t\
+{\
+	struct _name_t\
 	{\
-		struct _name_t\
+		static constexpr const char* _get_name() { return #name; }\
+		template<typename T>\
+		struct _member_t\
 		{\
-			static constexpr const char* _get_name() { return #name; }\
-			template<typename T>\
-			struct _member_t\
-			{\
-				T name;\
-				T& operator()() { return name; }\
-				const T& operator()() const { return name; }\
-			};\
+			T name;\
+			T& operator()() { return name; }\
+			const T& operator()() const { return name; }\
 		};\
 	};\
-	constexpr name##_t name = {};
+};\
+constexpr name##_t name = {};
 
 namespace sqlpp
 {

include/sqlpp11/all_of.h

@@ -34,36 +34,33 @@
 namespace sqlpp
 {
 	template<typename Table>
-	struct all_of_t
- 	{
-		using _column_tuple_t = typename Table::_column_tuple_t;
+		struct all_of_t
+		{
+			using _column_tuple_t = typename Table::_column_tuple_t;
 
-		template<typename AliasProvider>
-			detail::copy_tuple_args_t<multi_column_alias_t, AliasProvider, _column_tuple_t> as(const AliasProvider& alias)
-			{
-				return ::sqlpp::multi_column(_column_tuple_t{}).as(alias);
-			}
-	};
+			template<typename AliasProvider>
+				detail::copy_tuple_args_t<multi_column_alias_t, AliasProvider, _column_tuple_t> as(const AliasProvider& alias)
+				{
+					return ::sqlpp::multi_column(_column_tuple_t{}).as(alias);
+				}
+		};
 
 	template<typename Table>
-	auto all_of(Table t) -> all_of_t<Table>
-	{
-		return {};
-	}
+		auto all_of(Table t) -> all_of_t<Table>
+		{
+			return {};
+		}
 
-	namespace vendor
-	{
-		template<typename Context, typename Table>
-			struct serializer_t<Context, all_of_t<Table>>
+	template<typename Context, typename Table>
+		struct serializer_t<Context, all_of_t<Table>>
+		{
+			using T = all_of_t<Table>;
+
+			static Context& _(const T& t, const Context&)
 			{
-				using T = all_of_t<Table>;
-
-				static Context& _(const T& t, const Context&)
-				{
-					static_assert(wrong_t<T>::value, "all_of(table) does not seem to be used in select");
-				}
-			};
-	}
+				static_assert(wrong_t<T>::value, "all_of(table) does not seem to be used in select");
+			}
+		};
 
 }
 

include/sqlpp11/any.h

@@ -32,16 +32,11 @@
 
 namespace sqlpp
 {
-	namespace vendor
-	{
-		template<typename Select>
+	template<typename Select>
 		struct any_t
 		{
-			struct _value_type: public Select::_value_type::_base_value_type
-			{
-				using _is_expression = std::false_type;
-				using _is_multi_expression = std::true_type; // must not be named or used with +,-,*,/, etc
-			};
+			using _traits = make_traits<value_type_of<Select>, ::sqlpp::tag::multi_expression>;
+			using _recursive_traits = make_recursive_traits<Select>;
 
 			struct _name_t
 			{
@@ -55,8 +50,6 @@ namespace sqlpp
 					};
 			};
 
-			using _table_set = typename Select::_table_set;
-
 			any_t(Select select):
 				_select(select)
 			{}
@@ -69,33 +62,30 @@ namespace sqlpp
 
 			Select _select;
 		};
-	}
 
-	namespace vendor
-	{
-		template<typename Context, typename Select>
-			struct serializer_t<Context, vendor::any_t<Select>>
+	template<typename Context, typename Select>
+		struct serializer_t<Context, any_t<Select>>
+		{
+			using T = any_t<Select>;
+
+			static Context& _(const T& t, Context& context)
 			{
-				using T = vendor::any_t<Select>;
-
-				static Context& _(const T& t, Context& context)
-				{
-					context << "ANY(";
-					serialize(t._select, context);
-					context << ")";
-					return context;
-				}
-			};
-
-		template<typename T>
-			auto any(T t) -> typename vendor::any_t<vendor::wrap_operand_t<T>>
-			{
-				static_assert(is_select_t<vendor::wrap_operand_t<T>>::value, "any() requires a select expression as argument");
-				static_assert(is_value_t<vendor::wrap_operand_t<T>>::value, "any() requires a single column select expression as argument");
-				return { t };
+				context << "ANY(";
+				serialize(t._select, context);
+				context << ")";
+				return context;
 			}
+		};
+
+	template<typename T>
+		auto any(T t) -> any_t<wrap_operand_t<T>>
+		{
+			static_assert(is_select_t<wrap_operand_t<T>>::value, "any() requires a select expression as argument");
+			static_assert(is_expression_t<wrap_operand_t<T>>::value, "any() requires a single column select expression as argument");
+			// FIXME: can we accept non-values like NULL here?
+			return { t };
+		}
 
-	}
 }
 
 #endif

include/sqlpp11/assignment.h

@@ -0,0 +1,161 @@
+/*
+ * Copyright (c) 2013-2014, Roland Bock
+ * All rights reserved.
+ * 
+ * Redistribution and use in source and binary forms, with or without modification,
+ * are permitted provided that the following conditions are met:
+ * 
+ *   Redistributions of source code must retain the above copyright notice, this
+ *   list of conditions and the following disclaimer.
+ * 
+ *   Redistributions in binary form must reproduce the above copyright notice, this
+ *   list of conditions and the following disclaimer in the documentation and/or
+ *   other materials provided with the distribution.
+ * 
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR
+ * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+ * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef SQLPP_ASSIGNMENT_H
+#define SQLPP_ASSIGNMENT_H
+
+#include <sqlpp11/default_value.h>
+#include <sqlpp11/null.h>
+#include <sqlpp11/tvin.h>
+#include <sqlpp11/serialize.h>
+#include <sqlpp11/serializer.h>
+#include <sqlpp11/simple_column.h>
+
+namespace sqlpp
+{
+	template<typename T, typename Enable = void>
+		struct is_trivial_t
+		{
+			static constexpr bool _(const T&)
+			{
+				return false;
+			}
+		};
+
+	template<typename T>
+		struct is_trivial_t<T, typename std::enable_if<std::is_member_function_pointer<decltype(&T::_is_trivial)>::value, void>::type>
+		{
+			static bool _(const T& t)
+			{
+				return t._is_trivial();
+			}
+		};
+
+	template<typename T>
+		bool is_trivial(const T& t)
+		{
+			return is_trivial_t<T>::_(t);
+		}
+
+	template<typename Lhs, typename Rhs>
+		struct assignment_t
+		{
+			using _traits = make_traits<no_value_t, ::sqlpp::tag::assignment>;
+			using _recursive_traits = make_recursive_traits<Lhs, Rhs>;
+
+			using _column_t = Lhs;
+			using _value_t = Rhs;
+
+			static_assert(can_be_null_t<_column_t>::value ? true : not std::is_same<_value_t, null_t>::value, "column must not be null");
+
+			assignment_t(_column_t lhs, _value_t rhs):
+				_lhs(lhs), 
+				_rhs(rhs)
+			{}
+
+			assignment_t(const assignment_t&) = default;
+			assignment_t(assignment_t&&) = default;
+			assignment_t& operator=(const assignment_t&) = default;
+			assignment_t& operator=(assignment_t&&) = default;
+			~assignment_t() = default;
+
+			_column_t _lhs;
+			_value_t _rhs;
+		};
+
+	template<typename Context, typename Lhs, typename Rhs>
+		struct serializer_t<Context, assignment_t<Lhs, Rhs>>
+		{
+			using T = assignment_t<Lhs, Rhs>;
+
+			static Context& _(const T& t, Context& context)
+			{
+				if ((trivial_value_is_null_t<typename T::_column_t>::value
+							and is_trivial(t._rhs))
+						or (std::is_same<Rhs, null_t>::value))
+				{
+					serialize(simple_column(t._lhs), context);
+					context << "=NULL";
+				}
+				else
+				{
+					serialize(simple_column(t._lhs), context);
+					context << "=";
+					serialize(t._rhs, context);
+				}
+				return context;
+			}
+		};
+
+	template<typename Lhs, typename Rhs>
+		struct assignment_t<Lhs, tvin_t<Rhs>>
+		{
+			using _traits = make_traits<no_value_t, ::sqlpp::tag::assignment>;
+			using _recursive_traits = make_recursive_traits<Lhs, Rhs>;
+
+			using _column_t = Lhs;
+			using _value_t = tvin_t<Rhs>;
+
+			static_assert(can_be_null_t<_column_t>::value, "column cannot be null");
+
+			assignment_t(_column_t lhs, _value_t rhs):
+				_lhs(lhs), 
+				_rhs(rhs)
+			{}
+
+			assignment_t(const assignment_t&) = default;
+			assignment_t(assignment_t&&) = default;
+			assignment_t& operator=(const assignment_t&) = default;
+			assignment_t& operator=(assignment_t&&) = default;
+			~assignment_t() = default;
+
+			_column_t _lhs;
+			_value_t _rhs;
+		};
+
+	template<typename Context, typename Lhs, typename Rhs>
+		struct serializer_t<Context, assignment_t<Lhs, tvin_t<Rhs>>>
+		{
+			using T = assignment_t<Lhs, tvin_t<Rhs>>;
+
+			static Context& _(const T& t, Context& context)
+			{
+				serialize(simple_column(t._lhs), context);
+				if (t._rhs._value._is_trivial())
+				{
+					context << "=NULL";
+				}
+				else
+				{
+					context << "=";
+					serialize(t._rhs._value, context);
+				}
+				return context;
+			}
+		};
+}
+
+#endif

include/sqlpp11/avg.h

@@ -31,80 +31,71 @@
 
 namespace sqlpp
 {
-	namespace vendor
+	template<typename Flag, typename Expr>
+		struct avg_t: public floating_point::template expression_operators<avg_t<Flag, Expr>>,
+		public alias_operators<avg_t<Flag, Expr>>
 	{
-		template<typename Flag, typename Expr>
-		struct avg_t: public floating_point::template expression_operators<avg_t<Flag, Expr>>
+		using _traits = make_traits<floating_point, ::sqlpp::tag::expression, ::sqlpp::tag::named_expression>;
+		using _recursive_traits = make_recursive_traits<Expr>;
+
+		static_assert(is_noop<Flag>::value or std::is_same<sqlpp::distinct_t, Flag>::value, "avg() used with flag other than 'distinct'");
+		static_assert(is_numeric_t<Expr>::value, "avg() requires a value expression as argument");
+
+		struct _name_t
 		{
-			static_assert(is_noop<Flag>::value or std::is_same<sqlpp::distinct_t, Flag>::value, "avg() used with flag other than 'distinct'");
-			static_assert(is_numeric_t<Expr>::value, "avg() requires a value expression as argument");
-
-			struct _value_type: public floating_point
-			{
-				using _is_named_expression = std::true_type;
-			};
-
-			using _table_set = typename Expr::_table_set;
-
-			struct _name_t
-			{
-				static constexpr const char* _get_name() { return "AVG"; }
-				template<typename T>
-					struct _member_t
-					{
-						T avg;
-						T& operator()() { return avg; }
-						const T& operator()() const { return avg; }
-					};
-			};
-
-			avg_t(Expr expr):
-				_expr(expr)
-			{}
-
-			avg_t(const avg_t&) = default;
-			avg_t(avg_t&&) = default;
-			avg_t& operator=(const avg_t&) = default;
-			avg_t& operator=(avg_t&&) = default;
-			~avg_t() = default;
-
-			Expr _expr;
-		};
-	}
-
-	namespace vendor
-	{
-		template<typename Context, typename Flag, typename Expr>
-			struct serializer_t<Context, vendor::avg_t<Flag, Expr>>
-			{
-				using T = vendor::avg_t<Flag, Expr>;
-
-				static Context& _(const T& t, Context& context)
+			static constexpr const char* _get_name() { return "AVG"; }
+			template<typename T>
+				struct _member_t
 				{
-					context << "AVG(";
-					if (std::is_same<sqlpp::distinct_t, Flag>::value)
-					{
-						serialize(Flag(), context);
-						context << ' ';
-					}
-					serialize(t._expr, context);
-					context << ")";
-					return context;
+					T avg;
+					T& operator()() { return avg; }
+					const T& operator()() const { return avg; }
+				};
+		};
+
+		avg_t(Expr expr):
+			_expr(expr)
+		{}
+
+		avg_t(const avg_t&) = default;
+		avg_t(avg_t&&) = default;
+		avg_t& operator=(const avg_t&) = default;
+		avg_t& operator=(avg_t&&) = default;
+		~avg_t() = default;
+
+		Expr _expr;
+	};
+
+	template<typename Context, typename Flag, typename Expr>
+		struct serializer_t<Context, avg_t<Flag, Expr>>
+		{
+			using T = avg_t<Flag, Expr>;
+
+			static Context& _(const T& t, Context& context)
+			{
+				context << "AVG(";
+				if (std::is_same<sqlpp::distinct_t, Flag>::value)
+				{
+					serialize(Flag(), context);
+					context << ' ';
 				}
-			};
-	}
+				serialize(t._expr, context);
+				context << ")";
+				return context;
+			}
+		};
 
 	template<typename T>
-		auto avg(T t) -> typename vendor::avg_t<vendor::noop, vendor::wrap_operand_t<T>>
+		auto avg(T t) -> avg_t<noop, wrap_operand_t<T>>
 		{
-			static_assert(is_numeric_t<vendor::wrap_operand_t<T>>::value, "avg() requires a value expression as argument");
+			static_assert(is_numeric_t<wrap_operand_t<T>>::value, "avg() requires a value expression as argument");
 			return { t };
 		}
 
 	template<typename T>
-		auto avg(const sqlpp::distinct_t&, T t) -> typename vendor::avg_t<sqlpp::distinct_t, vendor::wrap_operand_t<T>>
+		auto avg(const sqlpp::distinct_t&, T t) -> avg_t<sqlpp::distinct_t, wrap_operand_t<T>>
 		{
-			static_assert(is_numeric_t<vendor::wrap_operand_t<T>>::value, "avg() requires a value expression as argument");
+			static_assert(is_numeric_t<wrap_operand_t<T>>::value, "avg() requires a value expression as argument");
 			return { t };
 		}
 

include/sqlpp11/basic_expression_operators.h

@@ -29,93 +29,88 @@
 
 #include <sqlpp11/alias.h>
 #include <sqlpp11/sort_order.h>
-#include <sqlpp11/vendor/expression_fwd.h>
-#include <sqlpp11/vendor/in_fwd.h>
-#include <sqlpp11/vendor/is_null_fwd.h>
+#include <sqlpp11/expression_fwd.h>
+#include <sqlpp11/in_fwd.h>
+#include <sqlpp11/is_null_fwd.h>
+#include <sqlpp11/wrap_operand.h>
 #include <sqlpp11/detail/logic.h>
 
 namespace sqlpp
 {
-
-	namespace detail
-	{
-		struct boolean;
-	}
-
 	// basic operators
 	template<typename Base, template<typename> class IsCorrectValueType>
 		struct basic_expression_operators
 		{
 			template<typename T>
 				struct _is_valid_comparison_operand
-			{
-				static constexpr bool value = 
-					(is_expression_t<T>::value // expressions are OK
-					or is_multi_expression_t<T>::value) // multi-expressions like ANY are OK for comparisons, too
-					and IsCorrectValueType<T>::value // the correct value type is required, of course
-					;
-			};
+				{
+					static constexpr bool value = 
+						(is_expression_t<T>::value // expressions are OK
+						 or is_multi_expression_t<T>::value) // multi-expressions like ANY are OK for comparisons, too
+						and IsCorrectValueType<T>::value // the correct value type is required, of course
+						;
+				};
 
 			template<typename T>
-				vendor::equal_to_t<Base, vendor::wrap_operand_t<T>> operator==(T t) const
+				equal_to_t<Base, wrap_operand_t<T>> operator==(T t) const
 				{
-					using rhs = vendor::wrap_operand_t<T>;
+					using rhs = wrap_operand_t<T>;
 					static_assert(_is_valid_comparison_operand<rhs>::value, "invalid rhs operand in comparison");
 
 					return { *static_cast<const Base*>(this), rhs{t} };
 				}
 
 			template<typename T>
-				vendor::not_equal_to_t<Base, vendor::wrap_operand_t<T>> operator!=(T t) const
+				not_equal_to_t<Base, wrap_operand_t<T>> operator!=(T t) const
 				{
-					using rhs = vendor::wrap_operand_t<T>;
+					using rhs = wrap_operand_t<T>;
 					static_assert(_is_valid_comparison_operand<rhs>::value, "invalid rhs operand in comparison");
 
 					return { *static_cast<const Base*>(this), rhs{t} };
 				}
 
 			template<typename T>
-				vendor::less_than_t<Base, vendor::wrap_operand_t<T>> operator<(T t) const
+				less_than_t<Base, wrap_operand_t<T>> operator<(T t) const
 				{
-					using rhs = vendor::wrap_operand_t<T>;
+					using rhs = wrap_operand_t<T>;
 					static_assert(_is_valid_comparison_operand<rhs>::value, "invalid rhs operand in comparison");
 
 					return { *static_cast<const Base*>(this), rhs{t} };
 				}
 
 			template<typename T>
-				vendor::less_equal_t<Base, vendor::wrap_operand_t<T>> operator<=(T t) const
+				less_equal_t<Base, wrap_operand_t<T>> operator<=(T t) const
 				{
-					using rhs = vendor::wrap_operand_t<T>;
+					using rhs = wrap_operand_t<T>;
 					static_assert(_is_valid_comparison_operand<rhs>::value, "invalid rhs operand in comparison");
 
 					return { *static_cast<const Base*>(this), rhs{t} };
 				}
 
 			template<typename T>
-				vendor::greater_than_t<Base, vendor::wrap_operand_t<T>> operator>(T t) const
+				greater_than_t<Base, wrap_operand_t<T>> operator>(T t) const
 				{
-					using rhs = vendor::wrap_operand_t<T>;
+					using rhs = wrap_operand_t<T>;
 					static_assert(_is_valid_comparison_operand<rhs>::value, "invalid rhs operand in comparison");
 
 					return { *static_cast<const Base*>(this), rhs{t} };
 				}
 
 			template<typename T>
-				vendor::greater_equal_t<Base, vendor::wrap_operand_t<T>> operator>=(T t) const
+				greater_equal_t<Base, wrap_operand_t<T>> operator>=(T t) const
 				{
-					using rhs = vendor::wrap_operand_t<T>;
+					using rhs = wrap_operand_t<T>;
 					static_assert(_is_valid_comparison_operand<rhs>::value, "invalid rhs operand in comparison");
 
 					return { *static_cast<const Base*>(this), rhs{t} };
 				}
 
-			vendor::is_null_t<true, Base> is_null() const
+			is_null_t<true, Base> is_null() const
 			{
 				return { *static_cast<const Base*>(this) };
 			}
 
-			vendor::is_null_t<false, Base> is_not_null() const
+			is_null_t<false, Base> is_not_null() const
 			{
 				return { *static_cast<const Base*>(this) };
 			}
@@ -132,19 +127,23 @@ namespace sqlpp
 
 			// Hint: use value_list wrapper for containers...
 			template<typename... T>
-				vendor::in_t<true, Base, vendor::wrap_operand_t<T>...> in(T... t) const
+				in_t<true, Base, wrap_operand_t<T>...> in(T... t) const
 				{
-					static_assert(detail::all_t<_is_valid_comparison_operand<vendor::wrap_operand_t<T>>::value...>::value, "at least one operand of in() is not valid");
-					return { *static_cast<const Base*>(this), vendor::wrap_operand_t<T>{t}... };
+					static_assert(detail::all_t<_is_valid_comparison_operand<wrap_operand_t<T>>::value...>::value, "at least one operand of in() is not valid");
+					return { *static_cast<const Base*>(this), wrap_operand_t<T>{t}... };
 				}
 
 			template<typename... T>
-				vendor::in_t<false, Base, vendor::wrap_operand_t<T>...> not_in(T... t) const
+				in_t<false, Base, wrap_operand_t<T>...> not_in(T... t) const
 				{
-					static_assert(detail::all_t<_is_valid_comparison_operand<vendor::wrap_operand_t<T>>::value...>::value, "at least one operand of in() is not valid");
-					return { *static_cast<const Base*>(this), vendor::wrap_operand_t<T>{t}... };
+					static_assert(detail::all_t<_is_valid_comparison_operand<wrap_operand_t<T>>::value...>::value, "at least one operand of in() is not valid");
+					return { *static_cast<const Base*>(this), wrap_operand_t<T>{t}... };
 				}
+		};
 
+	template<typename Base>
+		struct alias_operators
+		{
 			template<typename alias_provider>
 				expression_alias_t<Base, alias_provider> as(const alias_provider&)
 				{

include/sqlpp11/boolean.h

@@ -42,26 +42,22 @@ namespace sqlpp
 		// boolean value type
 		struct boolean
 		{
-			using _value_type = boolean;
-			using _base_value_type = boolean;
-			using _is_boolean = std::true_type;
-			using _is_value = std::true_type;
-			using _is_expression = std::true_type;
+			using _tag = ::sqlpp::tag::boolean;
 			using _cpp_value_type = bool;
 
 			struct _parameter_t
 			{
-				using _value_type = boolean;
+				using _value_type = boolean; // FIXME
 
 				_parameter_t():
 					_value(false),
 					_is_null(true)
-					{}
+				{}
 
 				_parameter_t(const _cpp_value_type& value):
 					_value(value),
 					_is_null(false)
-					{}
+				{}
 
 				_parameter_t& operator=(const _cpp_value_type& value)
 				{
@@ -78,7 +74,7 @@ namespace sqlpp
 				}
 
 				bool is_null() const
-			 	{ 
+				{ 
 					return _is_null; 
 				}
 
@@ -101,111 +97,98 @@ namespace sqlpp
 			};
 
 			template<typename Db, bool NullIsTrivial = false>
-			struct _result_entry_t
-			{
-				_result_entry_t():
-					_is_valid(false),
-					_is_null(true),
-					_value(false)
+				struct _result_entry_t
+				{
+					_result_entry_t():
+						_is_valid(false),
+						_is_null(true),
+						_value(false)
 					{}
 
-				_result_entry_t(const char* data, size_t):
-					_is_valid(true),
-					_is_null(data == nullptr),
-					_value(_is_null ? false : (data[0] == 't' or data[0] == '1'))
-					{}
-
-				void assign(const char* data, size_t)
-				{
-					_is_valid = true;
-					_is_null = data == nullptr;
-					_value = _is_null ? false : (data[0] == 't' or data[0] == '1');
-				}
-
-				void validate()
-				{
-					_is_valid = true;
-				}
-
-				void invalidate()
-				{
-					_is_valid = false;
-					_is_null = true;
-					_value = 0;
-				}
-
-				bool is_null() const
-			 	{ 
-					if (connector_assert_result_validity_t<Db>::value)
-						assert(_is_valid);
-					else if (not _is_valid)
-						throw exception("accessing is_null in non-existing row");
-					return _is_null; 
-				}
-
-				_cpp_value_type value() const
-				{
-					const bool null_value = _is_null and not NullIsTrivial and not connector_null_result_is_trivial_value_t<Db>::value;
-					if (connector_assert_result_validity_t<Db>::value)
+					void _validate()
 					{
-						assert(_is_valid);
-						assert(not null_value);
-					}
-					else
-					{
-						if (not _is_valid)
-							throw exception("accessing value in non-existing row");
-						if (null_value)
-							throw exception("accessing value of NULL field");
-					}
-					return _value;
-				}
-
-				operator _cpp_value_type() const { return value(); }
-
-				template<typename Target>
-					void _bind(Target& target, size_t i)
-					{
-						target._bind_boolean_result(i, &_value, &_is_null);
+						_is_valid = true;
 					}
 
-			private:
-				bool _is_valid;
-				bool _is_null;
-				signed char _value;
-			};
+					void _invalidate()
+					{
+						_is_valid = false;
+						_is_null = true;
+						_value = 0;
+					}
+
+					bool is_null() const
+					{ 
+						if (connector_assert_result_validity_t<Db>::value)
+							assert(_is_valid);
+						else if (not _is_valid)
+							throw exception("accessing is_null in non-existing row");
+						return _is_null; 
+					}
+
+					_cpp_value_type value() const
+					{
+						const bool null_value = _is_null and not NullIsTrivial and not connector_null_result_is_trivial_value_t<Db>::value;
+						if (connector_assert_result_validity_t<Db>::value)
+						{
+							assert(_is_valid);
+							assert(not null_value);
+						}
+						else
+						{
+							if (not _is_valid)
+								throw exception("accessing value in non-existing row");
+							if (null_value)
+								throw exception("accessing value of NULL field");
+						}
+						return _value;
+					}
+
+					operator _cpp_value_type() const { return value(); }
+
+					template<typename Target>
+						void _bind(Target& target, size_t i)
+						{
+							target._bind_boolean_result(i, &_value, &_is_null);
+						}
+
+				private:
+					bool _is_valid;
+					bool _is_null;
+					signed char _value;
+				};
 
 			template<typename T>
 				struct _is_valid_operand
-			{
-				static constexpr bool value = 
-					is_expression_t<T>::value // expressions are OK
-					and is_boolean_t<T>::value // the correct value type is required, of course
-					;
-			};
+				{
+					static constexpr bool value = 
+						is_expression_t<T>::value // expressions are OK
+						and is_boolean_t<T>::value // the correct value type is required, of course
+						;
+				};
 
 			template<typename Base>
 				struct expression_operators: public basic_expression_operators<Base, is_boolean_t>
 			{
 				template<typename T>
-					vendor::logical_and_t<Base, vendor::wrap_operand_t<T>> operator and(T t) const
+					logical_and_t<Base, wrap_operand_t<T>> operator and(T t) const
 					{
-						using rhs = vendor::wrap_operand_t<T>;
+						using rhs = wrap_operand_t<T>;
 						static_assert(_is_valid_operand<rhs>::value, "invalid rhs operand");
 
 						return { *static_cast<const Base*>(this), rhs{t} };
 					}
 
 				template<typename T>
-					vendor::logical_or_t<Base, vendor::wrap_operand_t<T>> operator or(T t) const
+					logical_or_t<Base, wrap_operand_t<T>> operator or(T t) const
 					{
-						using rhs = vendor::wrap_operand_t<T>;
+						using rhs = wrap_operand_t<T>;
 						static_assert(_is_valid_operand<rhs>::value, "invalid rhs operand");
 
 						return { *static_cast<const Base*>(this), rhs{t} };
 					}
 
-				vendor::logical_not_t<Base> operator not() const
+				logical_not_t<Base> operator not() const
 				{
 					return { *static_cast<const Base*>(this) };
 				}
@@ -213,15 +196,15 @@ namespace sqlpp
 
 			template<typename Base>
 				struct column_operators
-			{
-			};
+				{
+				};
 		};
 
 		template<typename Db, bool TrivialIsNull>
-		inline std::ostream& operator<<(std::ostream& os, const boolean::_result_entry_t<Db, TrivialIsNull>& e)
-		{
-			return os << e.value();
-		}
+			inline std::ostream& operator<<(std::ostream& os, const boolean::_result_entry_t<Db, TrivialIsNull>& e)
+			{
+				return os << e.value();
+			}
 	}
 
 	using boolean = detail::boolean;

include/sqlpp11/column.h

@@ -33,33 +33,34 @@
 #include <sqlpp11/null.h>
 #include <sqlpp11/sort_order.h>
 #include <sqlpp11/type_traits.h>
-#include <sqlpp11/vendor/assignment.h>
-#include <sqlpp11/vendor/expression.h>
-#include <sqlpp11/vendor/serializer.h>
-#include <sqlpp11/vendor/wrong.h>
+#include <sqlpp11/assignment.h>
+#include <sqlpp11/expression.h>
+#include <sqlpp11/serializer.h>
+#include <sqlpp11/wrong.h>
 #include <sqlpp11/detail/type_set.h>
 
 namespace sqlpp
 {
 	template<typename Table, typename ColumnSpec>
-	struct column_t: public ColumnSpec::_value_type::template expression_operators<column_t<Table, ColumnSpec>>,
-	                 public ColumnSpec::_value_type::template column_operators<column_t<Table, ColumnSpec>>
+		struct column_t: public ColumnSpec::_value_type::template expression_operators<column_t<Table, ColumnSpec>>,
+		public ColumnSpec::_value_type::template column_operators<column_t<Table, ColumnSpec>>
 	{ 
-		using _is_column = std::true_type;
+		using _traits = make_traits<typename ColumnSpec::_value_type, tag::column, tag::expression, tag::named_expression>;
+		struct _recursive_traits
+		{
+			using _parameters = std::tuple<>;
+			using _provided_tables = detail::type_set<>;
+			using _required_tables = detail::type_set<Table>;
+			using _extra_tables = detail::type_set<>;
+		};
+
 		using _spec_t = ColumnSpec;
 		using _table = Table;
-		using _table_set = detail::type_set<_table>;
-		using _column_type = typename ColumnSpec::_column_type;
-		struct _value_type: ColumnSpec::_value_type
-		{
-			using _is_expression = std::true_type;
-			using _is_named_expression = std::true_type;
-			using _is_alias = std::false_type;
-		};
-		template<typename T>
-			using _is_valid_operand = typename _value_type::template _is_valid_operand<T>;
+		using _column_type = typename _spec_t::_column_type;
+		using _name_t = typename _spec_t::_name_t;
 
-		using _name_t = typename ColumnSpec::_name_t;
+		template<typename T>
+			using _is_valid_operand = typename ColumnSpec::_value_type::template _is_valid_operand<T>;
 
 		column_t() = default;
 		column_t(const column_t&) = default;
@@ -80,43 +81,40 @@ namespace sqlpp
 			}
 
 		template<typename T>
-			auto operator =(T t) const -> vendor::assignment_t<column_t, typename vendor::wrap_operand<T>::type>
+			auto operator =(T t) const -> assignment_t<column_t, wrap_operand_t<T>>
 			{
-				using rhs = vendor::wrap_operand_t<T>;
+				using rhs = wrap_operand_t<T>;
 				static_assert(_is_valid_operand<rhs>::value, "invalid rhs operand assignment operand");
 
-				return { *this, {t} };
+				return { *this, rhs{t} };
 			}
 
 		auto operator =(sqlpp::null_t) const
-			->vendor::assignment_t<column_t, sqlpp::null_t>
+			->assignment_t<column_t, sqlpp::null_t>
 			{
 				static_assert(can_be_null_t<column_t>::value, "column cannot be null");
 				return { *this, {} };
 			}
 
 		auto operator =(sqlpp::default_value_t) const
-			->vendor::assignment_t<column_t, sqlpp::default_value_t>
+			->assignment_t<column_t, sqlpp::default_value_t>
 			{
 				return { *this, {} };
 			}
 	};
 
-	namespace vendor
-	{
-		template<typename Context, typename... Args>
-			struct serializer_t<Context, column_t<Args...>>
+	template<typename Context, typename... Args>
+		struct serializer_t<Context, column_t<Args...>>
+		{
+			using T = column_t<Args...>;
+
+			static Context& _(const T& t, Context& context)
 			{
-				using T = column_t<Args...>;
+				context << T::_table::_name_t::_get_name() << '.' << T::_name_t::_get_name();
+				return context;
+			}
+		};
 
-				static Context& _(const T& t, Context& context)
-				{
-					context << T::_table::_name_t::_get_name() << '.' << T::_name_t::_get_name();
-					return context;
-				}
-			};
-
-	}
 }
 
 #endif

include/sqlpp11/column_fwd.h

@@ -31,7 +31,7 @@
 namespace sqlpp
 {
 	template<typename Table, typename ColumnSpec>
-		class column_t;
+		struct column_t;
 }
 
 #endif

include/sqlpp11/concat.h

@@ -28,62 +28,58 @@
 #define SQLPP_CONCAT_H
 
 #include <sqlpp11/type_traits.h>
-#include <sqlpp11/vendor/interpret_tuple.h>
+#include <sqlpp11/interpret_tuple.h>
+#include <sqlpp11/basic_expression_operators.h>
 #include <sqlpp11/detail/logic.h>
 
 namespace sqlpp
 {
-	namespace vendor
+	// FIXME: Remove First, inherit from text_t
+	template<typename First, typename... Args>
+		struct concat_t: public value_type_of<First>::template expression_operators<concat_t<First, Args...>>,
+		public alias_operators<concat_t<First, Args...>>
 	{
-		template<typename First, typename... Args>
-			struct concat_t: public First::_value_type::template expression_operators<concat_t<First, Args...>>
+		using _traits = make_traits<value_type_of<First>, ::sqlpp::tag::expression, ::sqlpp::tag::named_expression>;
+		using _recursive_traits = make_recursive_traits<First, Args...>;
+
+		static_assert(sizeof...(Args) > 0, "concat requires two arguments at least");
+		static_assert(sqlpp::detail::all_t<is_text_t<First>::value, is_text_t<Args>::value...>::value, "at least one non-text argument detected in concat()");
+		struct _name_t
 		{
-			static_assert(sizeof...(Args) > 0, "concat requires two arguments at least");
-			static_assert(sqlpp::detail::all_t<is_text_t<First>::value, is_text_t<Args>::value...>::value, "at least one non-text argument detected in concat()");
-			using _table_set = typename ::sqlpp::detail::make_joined_set<typename First::_table_set, typename Args::_table_set...>::type;
-
-			struct _value_type: public First::_value_type::_base_value_type
-			{
-				using _is_named_expression = std::true_type;
-			};
-
-			struct _name_t
-			{
-				static constexpr const char* _get_name() { return "CONCAT"; }
-				template<typename T>
-					struct _member_t
-					{
-						T concat;
-					};
-			};
-
-			concat_t(First first, Args... args):
-				_args(first, args...)
-			{}
-
-			concat_t(const concat_t&) = default;
-			concat_t(concat_t&&) = default;
-			concat_t& operator=(const concat_t&) = default;
-			concat_t& operator=(concat_t&&) = default;
-			~concat_t() = default;
-
-			std::tuple<First, Args...> _args;
+			static constexpr const char* _get_name() { return "CONCAT"; }
+			template<typename T>
+				struct _member_t
+				{
+					T concat;
+				};
 		};
 
-		template<typename Context, typename First, typename... Args>
-			struct serializer_t<Context, concat_t<First, Args...>>
-			{
-				using T = concat_t<First, Args...>;
+		concat_t(First first, Args... args):
+			_args(first, args...)
+		{}
 
-				static Context& _(const T& t, Context& context)
-				{
-					context << "(";
-					interpret_tuple(t._args, "||", context);
-					context << ")";
-					return context;
-				}
-			};
-	}
+		concat_t(const concat_t&) = default;
+		concat_t(concat_t&&) = default;
+		concat_t& operator=(const concat_t&) = default;
+		concat_t& operator=(concat_t&&) = default;
+		~concat_t() = default;
+
+		std::tuple<First, Args...> _args;
+	};
+
+	template<typename Context, typename First, typename... Args>
+		struct serializer_t<Context, concat_t<First, Args...>>
+		{
+			using T = concat_t<First, Args...>;
+
+			static Context& _(const T& t, Context& context)
+			{
+				context << "(";
+				interpret_tuple(t._args, "||", context);
+				context << ")";
+				return context;
+			}
+		};
 }
 
 #endif

include/sqlpp11/count.h

@@ -32,80 +32,71 @@
 
 namespace sqlpp
 {
-	namespace vendor
+	template<typename Flag, typename Expr>
+		struct count_t: public sqlpp::detail::integral::template expression_operators<count_t<Flag, Expr>>,
+		public alias_operators<count_t<Flag, Expr>>
 	{
-		template<typename Flag, typename Expr>
-		struct count_t: public sqlpp::detail::integral::template expression_operators<count_t<Flag, Expr>>
+		using _traits = make_traits<::sqlpp::detail::integral, ::sqlpp::tag::expression, ::sqlpp::tag::named_expression>;
+		using _recursive_traits = make_recursive_traits<Expr>;
+
+		static_assert(is_noop<Flag>::value or std::is_same<sqlpp::distinct_t, Flag>::value, "count() used with flag other than 'distinct'");
+		static_assert(is_expression_t<Expr>::value, "count() requires a sql expression as argument");
+
+		struct _name_t
 		{
-			static_assert(is_noop<Flag>::value or std::is_same<sqlpp::distinct_t, Flag>::value, "count() used with flag other than 'distinct'");
-			static_assert(is_expression_t<Expr>::value, "count() requires a sql expression as argument");
-
-			struct _value_type: public sqlpp::detail::integral
-			{
-				using _is_named_expression = std::true_type;
-			};
-
-			using _table_set = typename Expr::_table_set;
-
-			struct _name_t
-			{
-				static constexpr const char* _get_name() { return "COUNT"; }
-				template<typename T>
-					struct _member_t
-					{
-						T count;
-						T& operator()() { return count; }
-						const T& operator()() const { return count; }
-					};
-			};
-
-			count_t(const Expr expr):
-				_expr(expr)
-			{}
-
-			count_t(const count_t&) = default;
-			count_t(count_t&&) = default;
-			count_t& operator=(const count_t&) = default;
-			count_t& operator=(count_t&&) = default;
-			~count_t() = default;
-
-			Expr _expr;
-		};
-	}
-
-	namespace vendor
-	{
-		template<typename Context, typename Flag, typename Expr>
-			struct serializer_t<Context, vendor::count_t<Flag, Expr>>
-			{
-				using T = vendor::count_t<Flag, Expr>;
-
-				static Context& _(const T& t, Context& context)
+			static constexpr const char* _get_name() { return "COUNT"; }
+			template<typename T>
+				struct _member_t
 				{
-					context << "COUNT(";
-					if (std::is_same<sqlpp::distinct_t, Flag>::value)
-					{
-						serialize(Flag(), context);
-						context << ' ';
-					}
-					serialize(t._expr, context);
-					context << ")";
-					return context;
+					T count;
+					T& operator()() { return count; }
+					const T& operator()() const { return count; }
+				};
+		};
+
+		count_t(const Expr expr):
+			_expr(expr)
+		{}
+
+		count_t(const count_t&) = default;
+		count_t(count_t&&) = default;
+		count_t& operator=(const count_t&) = default;
+		count_t& operator=(count_t&&) = default;
+		~count_t() = default;
+
+		Expr _expr;
+	};
+
+	template<typename Context, typename Flag, typename Expr>
+		struct serializer_t<Context, count_t<Flag, Expr>>
+		{
+			using T = count_t<Flag, Expr>;
+
+			static Context& _(const T& t, Context& context)
+			{
+				context << "COUNT(";
+				if (std::is_same<sqlpp::distinct_t, Flag>::value)
+				{
+					serialize(Flag(), context);
+					context << ' ';
 				}
-			};
-	}
+				serialize(t._expr, context);
+				context << ")";
+				return context;
+			}
+		};
 
 	template<typename T>
-		auto count(T t) -> typename vendor::count_t<vendor::noop, vendor::wrap_operand_t<T>>
+		auto count(T t) -> count_t<noop, wrap_operand_t<T>>
 		{
-			static_assert(is_expression_t<vendor::wrap_operand_t<T>>::value, "count() requires an expression as argument");
+			static_assert(is_expression_t<wrap_operand_t<T>>::value, "count() requires an expression as argument");
 			return { t };
 		}
 
 	template<typename T>
-		auto count(const sqlpp::distinct_t&, T t) -> typename vendor::count_t<sqlpp::distinct_t, vendor::wrap_operand_t<T>>
+		auto count(const sqlpp::distinct_t&, T t) -> count_t<sqlpp::distinct_t, wrap_operand_t<T>>
 		{
-			static_assert(is_expression_t<vendor::wrap_operand_t<T>>::value, "count() requires an expression as argument");
+			static_assert(is_expression_t<wrap_operand_t<T>>::value, "count() requires an expression as argument");
 			return { t };
 		}
 

include/sqlpp11/default_value.h

@@ -33,27 +33,23 @@ namespace sqlpp
 {
 	struct default_value_t
 	{
-		static constexpr bool _is_expression = true;
-		using _value_type = no_value_t;
-		using _table_set = ::sqlpp::detail::type_set<>;
+		using _traits = make_traits<no_value_t, tag::expression>;
+		using _recursive_traits = make_recursive_traits<>;
 
 		static constexpr bool _is_trivial() { return false; }
 	};
 
-	namespace vendor
-	{
-		template<typename Context>
-			struct serializer_t<Context, default_value_t>
-			{
-				using Operand = default_value_t;
+	template<typename Context>
+		struct serializer_t<Context, default_value_t>
+		{
+			using Operand = default_value_t;
 
-				static Context& _(const Operand& t, Context& context)
-				{
-					context << "DEFAULT";
-					return context;
-				}
-			};
-	}
+			static Context& _(const Operand& t, Context& context)
+			{
+				context << "DEFAULT";
+				return context;
+			}
+		};
 
 	constexpr default_value_t default_value = {};
 

include/sqlpp11/detail/column_index_sequence.h

@@ -49,7 +49,7 @@ namespace sqlpp
 			};
 
 		template<std::size_t LastIndex, std::size_t... Ints, typename AliasProvider, typename... Fields, typename... Rest>
-			struct make_column_index_sequence_impl<column_index_sequence<LastIndex, Ints...>, vendor::multi_field_t<AliasProvider, Fields...>, Rest...>
+			struct make_column_index_sequence_impl<column_index_sequence<LastIndex, Ints...>, multi_field_t<AliasProvider, Fields...>, Rest...>
 			{
 				using type = typename make_column_index_sequence_impl<column_index_sequence<LastIndex + sizeof...(Fields), Ints..., LastIndex + sizeof...(Fields)>, Rest...>::type;
 			};

include/sqlpp11/detail/copy_tuple_args.h

@@ -57,7 +57,7 @@ namespace sqlpp
 		template<template<typename, typename...> class Target, typename First, typename T>
 			struct copy_tuple_args_impl
 			{
-				static_assert(vendor::wrong_t<T>::value, "copy_tuple_args must be called with a tuple");
+				static_assert(wrong_t<T>::value, "copy_tuple_args must be called with a tuple");
 			};
 
 		template<template<typename First, typename...> class Target, typename First, typename... Args>

include/sqlpp11/detail/get_last.h

@@ -0,0 +1,60 @@
+/*
+ * Copyright (c) 2013-2014, Roland Bock
+ * All rights reserved.
+ * 
+ * Redistribution and use in source and binary forms, with or without modification,
+ * are permitted provided that the following conditions are met:
+ * 
+ *   Redistributions of source code must retain the above copyright notice, this
+ *   list of conditions and the following disclaimer.
+ * 
+ *   Redistributions in binary form must reproduce the above copyright notice, this
+ *   list of conditions and the following disclaimer in the documentation and/or
+ *   other materials provided with the distribution.
+ * 
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR
+ * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+ * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef SQLPP_DETAIL_GET_LAST_H
+#define SQLPP_DETAIL_GET_LAST_H
+
+#include <type_traits>
+
+namespace sqlpp
+{
+	namespace detail
+	{
+		template<template<typename> class Predicate, typename Default, typename... T>
+			struct get_last_if_impl;
+
+		template<template<typename> class Predicate, typename Default>
+			struct get_last_if_impl<Predicate, Default>
+			{
+				using type = Default;
+			};
+
+		template<template<typename> class Predicate, typename Default, typename T, typename... Rest>
+			struct get_last_if_impl<Predicate, Default, T, Rest...>
+			{
+				using rest = typename get_last_if_impl<Predicate, Default, Rest...>::type;
+				using type = typename std::conditional<std::is_same<rest, Default>::value and Predicate<T>::value,
+							T,
+							rest>::type;
+			};
+
+		template<template<typename> class Predicate, typename Default, typename... T>
+			using get_last_if = typename get_last_if_impl<Predicate, Default, T...>::type;
+	}
+}
+
+
+#endif

include/sqlpp11/detail/pick_arg.h

@@ -24,36 +24,35 @@
  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
-#ifndef SQLPP_VENDOR_POLICY_UPDATE_H
-#define SQLPP_VENDOR_POLICY_UPDATE_H
+#ifndef SQLPP_DETAIL_PICK_ARG_H
+#define SQLPP_DETAIL_PICK_ARG_H
 
-#include <sqlpp11/vendor/wrong.h>
+#include <type_traits>
 
 namespace sqlpp
 {
-	namespace vendor
+	namespace detail
 	{
-		template<typename Needle, typename Replacement>
-			struct policy_update_impl
+		template<typename Target, typename Statement, typename Term>
+			typename Target::_data_t pick_arg_impl(Statement statement, Term term, const std::true_type&)
 			{
-				template<typename T>
-					using _policy_t = typename std::conditional<std::is_same<Needle, T>::value, Replacement, T>::type;
+				return term;
 			};
 
-		template<typename T, typename Needle, typename Replacement>
-			using policy_update_t = typename policy_update_impl<Needle, Replacement>::template _policy_t<T>;
-
-		template<typename Original, typename Needle, typename Replacement>
-			struct update_policies_impl
+		template<typename Target, typename Statement, typename Term>
+			typename Target::_data_t pick_arg_impl(Statement statement, Term term, const std::false_type&)
 			{
-				using type = typename Original::template _policy_update_t<Needle, Replacement>;
+				return Target::_get_member(statement)._data;
 			};
 
-		template<typename Original, typename Needle, typename Replacement>
-			using update_policies_t = typename update_policies_impl<Original, Needle, Replacement>::type;
-
+		// Returns a statement's term either by picking the term from the statement or using the new term
+		template<typename Target, typename Statement, typename Term>
+			typename Target::_data_t pick_arg(Statement statement, Term term)
+			{
+				return pick_arg_impl<Target>(statement, term, std::is_same<typename Target::_data_t, Term>());
+			};
 	}
-
 }
 
+
 #endif

include/sqlpp11/detail/sum.h

@@ -24,26 +24,39 @@
  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
-#ifndef SQLPP_DETAIL_ARG_SELECTOR_H
-#define SQLPP_DETAIL_ARG_SELECTOR_H
+#ifndef SQLPP_DETAIL_SUM_H
+#define SQLPP_DETAIL_SUM_H
 
 namespace sqlpp
 {
 	namespace detail
 	{
-		template<typename Target>
-			struct arg_selector
+
+		/** a non-recursive C++14 version
+			template<typename... Args>
+			constexpr std::size_t sum(Args... args)
 			{
-				static Target _(Target, Target t) { return t; }
+			std::size_t result = 0;
 
-				template<typename X>
-					static Target _(X, Target t) { return t; }
+				using swallow = int[];
+				(void) swallow{(result += args, 0)...};
 
-				template<typename X>
-					static Target _(Target t, X) { return t; }
-			};
+				return result;
+			}
+			*/
+
+		constexpr std::size_t sum()
+		{
+			return 0;
+		}
+
+		template<typename Arg, typename... Rest>
+			constexpr std::size_t sum(Arg arg, Rest... rest)
+			{
+				return arg + sum(rest...);
+			}
 	}
 }
 
-
 #endif
+

include/sqlpp11/detail/type_set.h

@@ -29,7 +29,7 @@
 
 #include <tuple>
 #include <type_traits>
-#include <sqlpp11/vendor/wrong.h>
+#include <sqlpp11/wrong.h>
 #include <sqlpp11/detail/logic.h>
 
 namespace sqlpp
@@ -73,7 +73,7 @@ namespace sqlpp
 		template<typename E, typename SET>
 			struct is_element_of
 			{
-				static_assert(::sqlpp::vendor::wrong_t<E, SET>::value, "SET has to be a type set");
+				static_assert(::sqlpp::wrong_t<E, SET>::value, "SET has to be a type set");
 			};
 
 		template<typename E, typename... Elements>
@@ -85,7 +85,7 @@ namespace sqlpp
 		template<typename L, typename R>
 			struct joined_set
 			{
-				static_assert(::sqlpp::vendor::wrong_t<L, R>::value, "L and R have to be type sets");
+				static_assert(::sqlpp::wrong_t<L, R>::value, "L and R have to be type sets");
 			};
 
 		template<typename... LElements, typename... RElements>
@@ -100,7 +100,7 @@ namespace sqlpp
 		template<typename L, typename R>
 			struct is_superset_of
 			{
-				static_assert(::sqlpp::vendor::wrong_t<L, R>::value, "L and R have to be type sets");
+				static_assert(::sqlpp::wrong_t<L, R>::value, "L and R have to be type sets");
 			};
 
 		template<typename... LElements, typename... RElements>
@@ -118,7 +118,7 @@ namespace sqlpp
 		template<typename L, typename R>
 			struct is_disjunct_from
 			{
-				static_assert(::sqlpp::vendor::wrong_t<L, R>::value, "invalid argument for is_disjunct_from");
+				static_assert(::sqlpp::wrong_t<L, R>::value, "invalid argument for is_disjunct_from");
 			};
 
 		template<typename... LElements, typename... RElements>
@@ -157,6 +157,9 @@ namespace sqlpp
 				using type = typename make_type_set_if<Predicate, Rest...>::type::template insert_if<Predicate, T>::type;
 			};
 
+		template<template<typename> class Predicate, typename... T>
+			using make_type_set_if_t = typename make_type_set_if<Predicate, T...>::type;
+
 		template<template<typename> class Predicate, typename... T>
 			struct make_type_set_if_not
 			{
@@ -171,7 +174,7 @@ namespace sqlpp
 		template<typename... T>
 			struct make_joined_set
 			{
-				static_assert(::sqlpp::vendor::wrong_t<T...>::value, "invalid argument for joined set");
+				static_assert(::sqlpp::wrong_t<T...>::value, "invalid argument for joined set");
 			};
 
 		template<>
@@ -194,7 +197,7 @@ namespace sqlpp
 		template<typename Minuend, typename Subtrahend>
 			struct make_difference_set
 			{
-				static_assert(::sqlpp::vendor::wrong_t<Minuend, Subtrahend>::value, "invalid argument for difference set");
+				static_assert(::sqlpp::wrong_t<Minuend, Subtrahend>::value, "invalid argument for difference set");
 			};
 
 		template<typename... Minuends, typename... Subtrahends>
@@ -208,6 +211,24 @@ namespace sqlpp
 		template<typename Minuend, typename Subtrahend>
 			using make_difference_set_t = typename make_difference_set<Minuend, Subtrahend>::type;
 
+
+		template<template<typename> class Transformation, typename T>
+			struct transform_set
+			{
+				static_assert(::sqlpp::wrong_t<T>::value, "invalid argument for transform_set");
+			};
+
+		template<template<typename> class Transformation, typename... E>
+			struct transform_set<Transformation, type_set<E...>>
+			{
+				using type = typename make_type_set<Transformation<E>...>::type;
+			};
+
+		template<template<typename> class Transformation, typename T>
+			using transform_set_t = typename transform_set<Transformation, T>::type;
+
+
+
 	}
 }
 

include/sqlpp11/exists.h

@@ -31,68 +31,59 @@
 
 namespace sqlpp
 {
-	namespace vendor
+	template<typename Select>
+		struct exists_t: public boolean::template expression_operators<exists_t<Select>>,
+		public alias_operators<exists_t<Select>>
 	{
-		template<typename Select>
-		struct exists_t: public boolean::template expression_operators<exists_t<Select>>
+		using _traits = make_traits<boolean, ::sqlpp::tag::expression, ::sqlpp::tag::named_expression>;
+		using _recursive_traits = make_recursive_traits<Select>;
+
+		static_assert(is_select_t<Select>::value, "exists() requires a select expression as argument");
+
+		struct _name_t
 		{
-			static_assert(is_select_t<Select>::value, "exists() requires a select expression as argument");
-
-			struct _value_type: public boolean
-			{
-				using _is_named_expression = std::true_type;
-			};
-
-			using _table_set = typename Select::_table_set;
-
-			struct _name_t
-			{
-				static constexpr const char* _get_name() { return "EXISTS"; }
-				template<typename T>
-					struct _member_t
-					{
-						T exists;
-						T& operator()() { return exists; }
-						const T& operator()() const { return exists; }
-					};
-			};
-
-			exists_t(Select select):
-				_select(select)
-			{}
-
-			exists_t(const exists_t&) = default;
-			exists_t(exists_t&&) = default;
-			exists_t& operator=(const exists_t&) = default;
-			exists_t& operator=(exists_t&&) = default;
-			~exists_t() = default;
-
-			Select _select;
-		};
-	}
-
-	namespace vendor
-	{
-		template<typename Context, typename Select>
-			struct serializer_t<Context, vendor::exists_t<Select>>
-			{
-				using T = vendor::exists_t<Select>;
-
-				static Context& _(const T& t, Context& context)
+			static constexpr const char* _get_name() { return "EXISTS"; }
+			template<typename T>
+				struct _member_t
 				{
-					context << "EXISTS(";
-					serialize(t._select, context);
-					context << ")";
-					return context;
-				}
-			};
-	}
+					T exists;
+					T& operator()() { return exists; }
+					const T& operator()() const { return exists; }
+				};
+		};
+
+		exists_t(Select select):
+			_select(select)
+		{}
+
+		exists_t(const exists_t&) = default;
+		exists_t(exists_t&&) = default;
+		exists_t& operator=(const exists_t&) = default;
+		exists_t& operator=(exists_t&&) = default;
+		~exists_t() = default;
+
+		Select _select;
+	};
+
+	template<typename Context, typename Select>
+		struct serializer_t<Context, exists_t<Select>>
+		{
+			using T = exists_t<Select>;
+
+			static Context& _(const T& t, Context& context)
+			{
+				context << "EXISTS(";
+				serialize(t._select, context);
+				context << ")";
+				return context;
+			}
+		};
 
 
 	template<typename T>
-		auto exists(T t) -> typename vendor::exists_t<vendor::wrap_operand_t<T>>
+		auto exists(T t) -> exists_t<wrap_operand_t<T>>
 		{
-			static_assert(is_select_t<vendor::wrap_operand_t<T>>::value, "exists() requires a select expression as argument");
+			static_assert(is_select_t<wrap_operand_t<T>>::value, "exists() requires a select expression as argument");
 			return { t };
 		}
 

include/sqlpp11/expression.h

@@ -0,0 +1,239 @@
+/*
+ * Copyright (c) 2013-2014, Roland Bock
+ * All rights reserved.
+ * 
+ * Redistribution and use in source and binary forms, with or without modification,
+ * are permitted provided that the following conditions are met:
+ * 
+ *   Redistributions of source code must retain the above copyright notice, this
+ *   list of conditions and the following disclaimer.
+ * 
+ *   Redistributions in binary form must reproduce the above copyright notice, this
+ *   list of conditions and the following disclaimer in the documentation and/or
+ *   other materials provided with the distribution.
+ * 
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR
+ * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+ * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef SQLPP_EXPRESSION_H
+#define SQLPP_EXPRESSION_H
+
+#include <sqlpp11/alias.h>
+#include <sqlpp11/boolean.h>
+#include <sqlpp11/tvin.h>
+#include <sqlpp11/noop.h>
+#include <sqlpp11/expression_fwd.h>
+#include <sqlpp11/serializer.h>
+#include <sqlpp11/wrap_operand.h>
+
+namespace sqlpp
+{
+	template<typename Lhs, typename Rhs>
+		struct binary_expression_t<Lhs, op::equal_to, Rhs>: public ::sqlpp::detail::boolean::template expression_operators<binary_expression_t<Lhs, op::equal_to, Rhs>>,
+		public alias_operators<binary_expression_t<Lhs, op::equal_to, Rhs>>
+		{
+			using _traits = make_traits<boolean, sqlpp::tag::expression>;
+			using _recursive_traits = make_recursive_traits<Lhs, Rhs>;
+
+			binary_expression_t(Lhs lhs, Rhs rhs):
+				_lhs(lhs), 
+				_rhs(rhs)
+			{}
+
+			binary_expression_t(const binary_expression_t&) = default;
+			binary_expression_t(binary_expression_t&&) = default;
+			binary_expression_t& operator=(const binary_expression_t&) = default;
+			binary_expression_t& operator=(binary_expression_t&&) = default;
+			~binary_expression_t() = default;
+
+			Lhs _lhs;
+			maybe_tvin_t<Rhs> _rhs;
+		};
+
+	template<typename Context, typename Lhs, typename Rhs>
+		struct serializer_t<Context, equal_to_t<Lhs, Rhs>>
+		{
+			using T = equal_to_t<Lhs, Rhs>;
+
+			static Context& _(const T& t, Context& context)
+			{
+				context << "(";
+				serialize(t._lhs, context);
+				if (t._rhs._is_trivial())
+				{
+					context << " IS NULL";
+				}
+				else
+				{
+					context << "=";
+					serialize(t._rhs, context);
+				}
+				context << ")";
+				return context;
+			}
+		};
+
+	template<typename Lhs, typename Rhs>
+		struct binary_expression_t<Lhs, op::not_equal_to, Rhs>: public ::sqlpp::detail::boolean::template expression_operators<binary_expression_t<Lhs, op::not_equal_to, Rhs>>,
+		public alias_operators<binary_expression_t<Lhs, op::not_equal_to, Rhs>>
+		{
+			using _traits = make_traits<boolean, sqlpp::tag::expression>;
+			using _recursive_traits = make_recursive_traits<Lhs, Rhs>;
+
+			binary_expression_t(Lhs lhs, Rhs rhs):
+				_lhs(lhs), 
+				_rhs(rhs)
+			{}
+
+			binary_expression_t(const binary_expression_t&) = default;
+			binary_expression_t(binary_expression_t&&) = default;
+			binary_expression_t& operator=(const binary_expression_t&) = default;
+			binary_expression_t& operator=(binary_expression_t&&) = default;
+			~binary_expression_t() = default;
+
+			Lhs _lhs;
+			maybe_tvin_t<Rhs> _rhs;
+		};
+
+	template<typename Context, typename Lhs, typename Rhs>
+		struct serializer_t<Context, not_equal_to_t<Lhs, Rhs>>
+		{
+			using T = not_equal_to_t<Lhs, Rhs>;
+
+			static Context& _(const T& t, Context& context)
+			{
+				context << "(";
+				serialize(t._lhs, context);
+				if (t._rhs._is_trivial())
+				{
+					context << " IS NOT NULL";
+				}
+				else
+				{
+					context << "!=";
+					serialize(t._rhs, context);
+				}
+				context << ")";
+				return context;
+			}
+		};
+
+	template<typename Rhs>
+		struct unary_expression_t<op::logical_not, Rhs>: public ::sqlpp::detail::boolean::template expression_operators<unary_expression_t<op::logical_not, Rhs>>,
+		public alias_operators<unary_expression_t<op::logical_not, Rhs>>
+		{
+			using _traits = make_traits<boolean, sqlpp::tag::expression>;
+			using _recursive_traits = make_recursive_traits<Rhs>;
+
+			unary_expression_t(Rhs rhs):
+				_rhs(rhs)
+			{}
+
+			unary_expression_t(const unary_expression_t&) = default;
+			unary_expression_t(unary_expression_t&&) = default;
+			unary_expression_t& operator=(const unary_expression_t&) = default;
+			unary_expression_t& operator=(unary_expression_t&&) = default;
+			~unary_expression_t() = default;
+
+			Rhs _rhs;
+		};
+
+	template<typename Context, typename Rhs>
+		struct serializer_t<Context, logical_not_t<Rhs>>
+		{
+			using T = logical_not_t<Rhs>;
+
+			static Context& _(const T& t, Context& context)
+			{
+				context << "(";
+				context << "NOT ";
+				serialize(t._lhs, context);
+				context << ")";
+				return context;
+			}
+		};
+
+	template<typename Lhs, typename O, typename Rhs>
+		struct binary_expression_t: public value_type_of<O>::template expression_operators<binary_expression_t<Lhs, O, Rhs>>,
+		public alias_operators<binary_expression_t<Lhs, O, Rhs>>
+	{
+		using _traits = make_traits<value_type_of<O>, sqlpp::tag::expression>;
+		using _recursive_traits = make_recursive_traits<Lhs, Rhs>;
+
+		binary_expression_t(Lhs lhs, Rhs rhs):
+			_lhs(lhs), 
+			_rhs(rhs)
+		{}
+
+		binary_expression_t(const binary_expression_t&) = default;
+		binary_expression_t(binary_expression_t&&) = default;
+		binary_expression_t& operator=(const binary_expression_t&) = default;
+		binary_expression_t& operator=(binary_expression_t&&) = default;
+		~binary_expression_t() = default;
+
+		Lhs _lhs;
+		Rhs _rhs;
+	};
+
+	template<typename Context, typename Lhs, typename O, typename Rhs>
+		struct serializer_t<Context, binary_expression_t<Lhs, O, Rhs>>
+		{
+			using T = binary_expression_t<Lhs, O, Rhs>;
+
+			static Context& _(const T& t, Context& context)
+			{
+				context << "(";
+				serialize(t._lhs, context);
+				context << O::_name;
+				serialize(t._rhs, context);
+				context << ")";
+				return context;
+			}
+		};
+
+	template<typename O, typename Rhs>
+		struct unary_expression_t: public value_type_of<O>::template expression_operators<unary_expression_t<O, Rhs>>,
+		public alias_operators<unary_expression_t<O, Rhs>>
+	{
+		using _traits = make_traits<value_type_of<O>, sqlpp::tag::expression>;
+		using _recursive_traits = make_recursive_traits<Rhs>;
+
+		unary_expression_t(Rhs rhs):
+			_rhs(rhs)
+		{}
+
+		unary_expression_t(const unary_expression_t&) = default;
+		unary_expression_t(unary_expression_t&&) = default;
+		unary_expression_t& operator=(const unary_expression_t&) = default;
+		unary_expression_t& operator=(unary_expression_t&&) = default;
+		~unary_expression_t() = default;
+
+		Rhs _rhs;
+	};
+
+	template<typename Context, typename O, typename Rhs>
+		struct serializer_t<Context, unary_expression_t<O, Rhs>>
+		{
+			using T = unary_expression_t<O, Rhs>;
+
+			static Context& _(const T& t, Context& context)
+			{
+				context << "(";
+				context << O::_name;
+				serialize(t._rhs, context);
+				context << ")";
+				return context;
+			}
+		};
+}
+
+#endif

include/sqlpp11/expression_fwd.h

@@ -0,0 +1,196 @@
+/*
+ * Copyright (c) 2013-2014, Roland Bock
+ * All rights reserved.
+ * 
+ * Redistribution and use in source and binary forms, with or without modification,
+ * are permitted provided that the following conditions are met:
+ * 
+ *   Redistributions of source code must retain the above copyright notice, this
+ *   list of conditions and the following disclaimer.
+ * 
+ *   Redistributions in binary form must reproduce the above copyright notice, this
+ *   list of conditions and the following disclaimer in the documentation and/or
+ *   other materials provided with the distribution.
+ * 
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR
+ * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+ * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef SQLPP_EXPRESSION_FWD_H
+#define SQLPP_EXPRESSION_FWD_H
+
+namespace sqlpp
+{
+	namespace detail
+	{
+		struct boolean;
+		struct integral;
+		struct floating_point;
+	}
+
+	namespace op
+	{
+		struct less
+		{
+			using _traits = make_traits<::sqlpp::detail::boolean>;
+			static constexpr const char* _name = "<";
+		};
+
+		struct less_equal
+		{
+			using _traits = make_traits<::sqlpp::detail::boolean>;
+			static constexpr const char* _name = "<=";
+		};
+
+		struct equal_to
+		{
+			using _traits = make_traits<::sqlpp::detail::boolean>;
+		};
+
+		struct not_equal_to
+		{
+			using _traits = make_traits<::sqlpp::detail::boolean>;
+		};
+
+		struct greater_equal
+		{
+			using _traits = make_traits<::sqlpp::detail::boolean>;
+			static constexpr const char* _name = ">=";
+		};
+
+		struct greater
+		{
+			using _traits = make_traits<::sqlpp::detail::boolean>;
+			static constexpr const char* _name = ">";
+		};
+
+		struct logical_or
+		{
+			using _traits = make_traits<::sqlpp::detail::boolean>;
+			static constexpr const char* _name = " OR ";
+		};
+
+		struct logical_and
+		{
+			using _traits = make_traits<::sqlpp::detail::boolean>;
+			static constexpr const char* _name = " AND ";
+		};
+
+		struct logical_not
+		{
+			using _traits = make_traits<::sqlpp::detail::boolean>;
+		};
+
+		template<typename ValueType>
+			struct plus
+			{
+				using _traits = make_traits<ValueType>;
+				static constexpr const char* _name = "+";
+			};
+
+		template<typename ValueType>
+			struct minus
+			{
+				using _traits = make_traits<ValueType>;
+				static constexpr const char* _name = "-";
+			};
+
+		template<typename ValueType>
+			struct multiplies
+			{
+				using _traits = make_traits<ValueType>;
+				static constexpr const char* _name = "*";
+			};
+
+		struct divides
+		{
+			using _traits = make_traits<::sqlpp::detail::floating_point>;
+			static constexpr const char* _name = "/";
+		};
+
+		struct modulus
+		{
+			using _traits = make_traits<::sqlpp::detail::integral>;
+			static constexpr const char* _name = "%";
+		};
+
+		template<typename ValueType>
+			struct unary_minus
+			{
+				using _traits = make_traits<ValueType>;
+				static constexpr const char* _name = "-";
+			};
+
+		template<typename ValueType>
+			struct unary_plus
+			{
+				using _traits = make_traits<ValueType>;
+				static constexpr const char* _name = "+";
+			};
+	}
+
+	template<typename Lhs, typename O, typename Rhs>
+		struct binary_expression_t;
+
+	template<typename O, typename Rhs>
+		struct unary_expression_t;
+
+	template<typename Lhs, typename Rhs>
+		using less_than_t = binary_expression_t<Lhs, op::less, Rhs>;
+
+	template<typename Lhs, typename Rhs>
+		using less_equal_t = binary_expression_t<Lhs, op::less_equal, Rhs>;
+
+	template<typename Lhs, typename Rhs>
+		using equal_to_t = binary_expression_t<Lhs, op::equal_to, Rhs>;
+
+	template<typename Lhs, typename Rhs>
+		using not_equal_to_t = binary_expression_t<Lhs, op::not_equal_to, Rhs>;
+
+	template<typename Lhs, typename Rhs>
+		using greater_than_t = binary_expression_t<Lhs, op::greater, Rhs>;
+
+	template<typename Lhs, typename Rhs>
+		using greater_equal_t = binary_expression_t<Lhs, op::greater_equal, Rhs>;
+
+	template<typename Lhs, typename Rhs>
+		using logical_and_t = binary_expression_t<Lhs, op::logical_and, Rhs>;
+
+	template<typename Lhs, typename Rhs>
+		using logical_or_t = binary_expression_t<Lhs, op::logical_or, Rhs>;
+
+	template<typename Lhs, typename ValueType, typename Rhs>
+		using plus_t = binary_expression_t<Lhs, op::plus<ValueType>, Rhs>;
+
+	template<typename Lhs, typename ValueType, typename Rhs>
+		using minus_t = binary_expression_t<Lhs, op::minus<ValueType>, Rhs>;
+
+	template<typename Lhs, typename ValueType, typename Rhs>
+		using multiplies_t = binary_expression_t<Lhs, op::multiplies<ValueType>, Rhs>;
+
+	template<typename Lhs, typename Rhs>
+		using divides_t = binary_expression_t<Lhs, op::divides, Rhs>;
+
+	template<typename Lhs, typename Rhs>
+		using modulus_t = binary_expression_t<Lhs, op::modulus, Rhs>;
+
+	template<typename Rhs>
+		using logical_not_t = unary_expression_t<op::logical_not, Rhs>;
+
+	template<typename ValueType, typename Rhs>
+		using unary_plus_t = unary_expression_t<op::unary_plus<ValueType>, Rhs>;
+
+	template<typename ValueType, typename Rhs>
+		using unary_minus_t = unary_expression_t<op::unary_minus<ValueType>, Rhs>;
+
+}
+
+#endif

include/sqlpp11/extra_tables.h

@@ -0,0 +1,168 @@
+/*
+ * Copyright (c) 2013-2014, Roland Bock
+ * All rights reserved.
+ * 
+ * Redistribution and use in source and binary forms, with or without modification,
+ * are permitted provided that the following conditions are met:
+ * 
+ *   Redistributions of source code must retain the above copyright notice, this
+ *   list of conditions and the following disclaimer.
+ * 
+ *   Redistributions in binary form must reproduce the above copyright notice, this
+ *   list of conditions and the following disclaimer in the documentation and/or
+ *   other materials provided with the distribution.
+ * 
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR
+ * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+ * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef SQLPP_EXTRA_TABLES_H
+#define SQLPP_EXTRA_TABLES_H
+
+#include <sqlpp11/type_traits.h>
+#include <sqlpp11/detail/logic.h>
+#include <sqlpp11/policy_update.h>
+
+namespace sqlpp
+{
+	template<typename... Tables>
+		struct extra_tables_data_t
+		{
+			extra_tables_data_t()
+			{}
+
+			extra_tables_data_t(const extra_tables_data_t&) = default;
+			extra_tables_data_t(extra_tables_data_t&&) = default;
+			extra_tables_data_t& operator=(const extra_tables_data_t&) = default;
+			extra_tables_data_t& operator=(extra_tables_data_t&&) = default;
+			~extra_tables_data_t() = default;
+
+		};
+
+	// EXTRA_TABLES
+	template<typename... Tables>
+		struct extra_tables_t
+		{
+			using _traits = make_traits<no_value_t, ::sqlpp::tag::extra_tables>;
+			struct _recursive_traits
+			{
+				using _parameters = std::tuple<>;
+				using _required_tables = ::sqlpp::detail::type_set<>;
+				using _provided_tables = ::sqlpp::detail::type_set<>;
+				using _extra_tables = ::sqlpp::detail::type_set<Tables...>;
+			};
+
+			// FIXME: extra_tables must not require tables!
+
+			static_assert(sizeof...(Tables), "at least one table or join argument required in extra_tables()");
+			static_assert(not ::sqlpp::detail::has_duplicates<Tables...>::value, "at least one duplicate argument detected in extra_tables()");
+			static_assert(::sqlpp::detail::all_t<is_table_t<Tables>::value...>::value, "at least one argument is not a table or join in extra_tables()");
+
+			// Data
+			using _data_t = extra_tables_data_t<Tables...>;
+
+			// Member implementation with data and methods
+			template <typename Policies>
+				struct _impl_t
+				{
+					_data_t _data;
+				};
+
+			// Member template for adding the named member to a statement
+			template<typename Policies>
+				struct _member_t
+				{
+					using _data_t = extra_tables_data_t<Tables...>;
+
+					_impl_t<Policies> extra_tables;
+					_impl_t<Policies>& operator()() { return extra_tables; }
+					const _impl_t<Policies>& operator()() const { return extra_tables; }
+
+					template<typename T>
+						static auto _get_member(T t) -> decltype(t.extra_tables)
+						{
+							return t.extra_tables;
+						}
+				};
+
+			// Additional methods for the statement
+			template<typename Policies>
+				struct _methods_t
+				{
+					static void _check_consistency() {}
+				};
+		};
+
+	// NO EXTRA TABLES YET
+	struct no_extra_tables_t
+	{
+		using _traits = make_traits<no_value_t, ::sqlpp::tag::noop>;
+		using _recursive_traits = make_recursive_traits<>;
+
+		// Data
+		using _data_t = no_data_t;
+
+		// Member implementation with data and methods
+		template<typename Policies>
+			struct _impl_t
+			{
+				_data_t _data;
+			};
+
+		// Member template for adding the named member to a statement
+		template<typename Policies>
+			struct _member_t
+			{
+				using _data_t = no_data_t;
+
+				_impl_t<Policies> no_extra_tables;
+				_impl_t<Policies>& operator()() { return no_extra_tables; }
+				const _impl_t<Policies>& operator()() const { return no_extra_tables; }
+
+				template<typename T>
+					static auto _get_member(T t) -> decltype(t.no_extra_tables)
+					{
+						return t.no_extra_tables;
+					}
+			};
+
+		template<typename Policies>
+			struct _methods_t
+			{
+				template<typename T>
+					using _new_statement_t = typename Policies::template _new_statement_t<no_extra_tables_t, T>;
+
+				static void _check_consistency() {}
+
+				template<typename... Args>
+					auto extra_tables(Args...)
+					-> _new_statement_t<extra_tables_t<Args...>>
+					{
+						return { *static_cast<typename Policies::_statement_t*>(this), extra_tables_data_t<Args...>{} };
+					}
+			};
+	};
+
+	// Interpreters
+	template<typename Context, typename Database, typename... Tables>
+		struct serializer_t<Context, extra_tables_data_t<Database, Tables...>>
+		{
+			using T = extra_tables_data_t<Database, Tables...>;
+
+			static Context& _(const T& t, Context& context)
+			{
+				return context;
+			}
+		};
+
+}
+
+#endif

include/sqlpp11/field.h

@@ -31,42 +31,41 @@
 
 namespace sqlpp
 {
-	namespace vendor
-	{
-		template<typename NameType, typename ValueType, bool TrivialValueIsNull>
-			struct field_t
-			{ 
-				using _name_t = NameType;
-				using _value_type = ValueType;
-				static constexpr bool _trivial_value_is_null = TrivialValueIsNull;
-			};
+	template<typename NameType, typename ValueType, bool TrivialValueIsNull>
+		struct field_t
+		{ 
+			using _traits = make_traits<ValueType, tag::noop>;
+			using _recursive_traits = make_recursive_traits<>;
 
-		template<typename AliasProvider, typename FieldTuple>
-			struct multi_field_t
-			{
-			};
+			using _name_t = NameType;
+			static constexpr bool _trivial_value_is_null = TrivialValueIsNull;
+		};
 
-		namespace detail
+	template<typename AliasProvider, typename FieldTuple>
+		struct multi_field_t
 		{
-			template<typename NamedExpr>
-				struct make_field_t_impl
-				{
-					using type = field_t<typename NamedExpr::_name_t, 
-								typename NamedExpr::_value_type::_base_value_type,
-								trivial_value_is_null_t<NamedExpr>::value>;
-				};
-
-			template<typename AliasProvider, typename... NamedExpr>
-				struct make_field_t_impl<multi_column_alias_t<AliasProvider, NamedExpr...>>
-				{
-					using type = multi_field_t<AliasProvider, std::tuple<typename make_field_t_impl<NamedExpr>::type...>>;
-				};
-		}
+		};
 
+	namespace detail
+	{
 		template<typename NamedExpr>
-			using make_field_t = typename detail::make_field_t_impl<NamedExpr>::type;
+			struct make_field_t_impl
+			{
+				using type = field_t<typename NamedExpr::_name_t, 
+							value_type_of<NamedExpr>,
+							trivial_value_is_null_t<NamedExpr>::value>;
+			};
+
+		template<typename AliasProvider, typename... NamedExpr>
+			struct make_field_t_impl<multi_column_alias_t<AliasProvider, NamedExpr...>>
+			{
+				using type = multi_field_t<AliasProvider, std::tuple<typename make_field_t_impl<NamedExpr>::type...>>;
+			};
 	}
 
+	template<typename NamedExpr>
+		using make_field_t = typename detail::make_field_t_impl<NamedExpr>::type;
+
 }
 
 #endif

include/sqlpp11/floating_point.h

@@ -41,27 +41,22 @@ namespace sqlpp
 		// floating_point value type
 		struct floating_point
 		{
-			using _value_type = floating_point;
-			using _base_value_type = floating_point;
-			using _is_numeric = std::true_type;
-			using _is_floating_point = std::true_type;
-			using _is_value = std::true_type;
-			using _is_expression = std::true_type;
+			using _tag = ::sqlpp::tag::floating_point;
 			using _cpp_value_type = double;
-			
+
 			struct _parameter_t
 			{
-				using _value_type = integral;
+				using _value_type = floating_point;
 
 				_parameter_t():
 					_value(0),
 					_is_null(true)
-					{}
+				{}
 
 				_parameter_t(const _cpp_value_type& value):
 					_value(value),
 					_is_null(false)
-					{}
+				{}
 
 				_parameter_t& operator=(const _cpp_value_type& value)
 				{
@@ -78,7 +73,7 @@ namespace sqlpp
 				}
 
 				bool is_null() const
-			 	{ 
+				{ 
 					return _is_null; 
 				}
 
@@ -101,134 +96,121 @@ namespace sqlpp
 			};
 
 			template<typename Db, bool NullIsTrivial = false>
-			struct _result_entry_t
-			{
-				using _value_type = integral;
+				struct _result_entry_t
+				{
+					using _value_type = integral;
 
-				_result_entry_t():
-					_is_valid(false),
-					_is_null(true),
-					_value(0)
+					_result_entry_t():
+						_is_valid(false),
+						_is_null(true),
+						_value(0)
 					{}
 
-				_result_entry_t(const char* data, size_t):
-					_is_valid(true),
-					_is_null(data == nullptr),
-					_value(_is_null ? 0 : std::strtoll(data, nullptr, 10))
-					{}
-
-				void assign(const char* data, size_t)
-				{
-					_is_valid = true;
-					_is_null = data == nullptr;
-					_value = _is_null ? 0 : std::strtoll(data, nullptr, 10);
-				}
-
-				void validate()
-				{
-					_is_valid = true;
-				}
-
-				void invalidate()
-				{
-					_is_valid = false;
-					_is_null = true;
-					_value = 0;
-				}
-
-				bool is_null() const
-			 	{ 
-					if (connector_assert_result_validity_t<Db>::value)
-						assert(_is_valid);
-					else if (not _is_valid)
-						throw exception("accessing is_null in non-existing row");
-					return _is_null; 
-				}
-
-				_cpp_value_type value() const
-				{
-					const bool null_value = _is_null and not NullIsTrivial and not connector_null_result_is_trivial_value_t<Db>::value;
-					if (connector_assert_result_validity_t<Db>::value)
+					void _validate()
 					{
-						assert(_is_valid);
-						assert(not null_value);
-					}
-					else
-					{
-						if (not _is_valid)
-							throw exception("accessing value in non-existing row");
-						if (null_value)
-							throw exception("accessing value of NULL field");
-					}
-					return _value;
-				}
-
-				operator _cpp_value_type() const { return value(); }
-
-				template<typename Target>
-					void _bind(Target& target, size_t i)
-					{
-						target._bind_floating_point_result(i, &_value, &_is_null);
+						_is_valid = true;
 					}
 
-			private:
-				bool _is_valid;
-				bool _is_null;
-				_cpp_value_type _value;
-			};
+					void _invalidate()
+					{
+						_is_valid = false;
+						_is_null = true;
+						_value = 0;
+					}
+
+					bool is_null() const
+					{ 
+						if (connector_assert_result_validity_t<Db>::value)
+							assert(_is_valid);
+						else if (not _is_valid)
+							throw exception("accessing is_null in non-existing row");
+						return _is_null; 
+					}
+
+					_cpp_value_type value() const
+					{
+						const bool null_value = _is_null and not NullIsTrivial and not connector_null_result_is_trivial_value_t<Db>::value;
+						if (connector_assert_result_validity_t<Db>::value)
+						{
+							assert(_is_valid);
+							assert(not null_value);
+						}
+						else
+						{
+							if (not _is_valid)
+								throw exception("accessing value in non-existing row");
+							if (null_value)
+								throw exception("accessing value of NULL field");
+						}
+						return _value;
+					}
+
+					operator _cpp_value_type() const { return value(); }
+
+					template<typename Target>
+						void _bind(Target& target, size_t i)
+						{
+							target._bind_floating_point_result(i, &_value, &_is_null);
+						}
+
+				private:
+					bool _is_valid;
+					bool _is_null;
+					_cpp_value_type _value;
+				};
 
 			template<typename T>
 				struct _is_valid_operand
-			{
-				static constexpr bool value = 
-					is_expression_t<T>::value // expressions are OK
-					and is_numeric_t<T>::value // the correct value type is required, of course
-					;
-			};
+				{
+					static constexpr bool value = 
+						is_expression_t<T>::value // expressions are OK
+						and is_numeric_t<T>::value // the correct value type is required, of course
+						;
+				};
 
 			template<typename Base>
 				struct expression_operators: public basic_expression_operators<Base, is_numeric_t>
 			{
 				template<typename T>
-					vendor::plus_t<Base, floating_point, vendor::wrap_operand_t<T>> operator +(T t) const
+					plus_t<Base, floating_point, wrap_operand_t<T>> operator +(T t) const
 					{
-						using rhs = vendor::wrap_operand_t<T>;
+						using rhs = wrap_operand_t<T>;
 						static_assert(_is_valid_operand<rhs>::value, "invalid rhs operand");
 
 						return { *static_cast<const Base*>(this), rhs{t} };
 					}
 
 				template<typename T>
-					vendor::minus_t<Base, floating_point, vendor::wrap_operand_t<T>> operator -(T t) const
+					minus_t<Base, floating_point, wrap_operand_t<T>> operator -(T t) const
 					{
-						using rhs = vendor::wrap_operand_t<T>;
+						using rhs = wrap_operand_t<T>;
 						static_assert(_is_valid_operand<rhs>::value, "invalid rhs operand");
 
 						return { *static_cast<const Base*>(this), rhs{t} };
 					}
 
 				template<typename T>
-					vendor::multiplies_t<Base, floating_point, vendor::wrap_operand_t<T>> operator *(T t) const
+					multiplies_t<Base, floating_point, wrap_operand_t<T>> operator *(T t) const
 					{
-						using rhs = vendor::wrap_operand_t<T>;
+						using rhs = wrap_operand_t<T>;
 
 						return { *static_cast<const Base*>(this), rhs{t} };
 					}
 
 				template<typename T>
-					vendor::divides_t<Base, vendor::wrap_operand_t<T>> operator /(T t) const
+					divides_t<Base, wrap_operand_t<T>> operator /(T t) const
 					{
-						using rhs = vendor::wrap_operand_t<T>;
+						using rhs = wrap_operand_t<T>;
 
 						return { *static_cast<const Base*>(this), rhs{t} };
 					}
 
-				vendor::unary_plus_t<floating_point, Base> operator +() const
+				unary_plus_t<floating_point, Base> operator +() const
 				{
 					return { *static_cast<const Base*>(this) };
 				}
 
-				vendor::unary_minus_t<floating_point, Base> operator -() const
+				unary_minus_t<floating_point, Base> operator -() const
 				{
 					return { *static_cast<const Base*>(this) };
 				}
@@ -236,50 +218,50 @@ namespace sqlpp
 
 			template<typename Base>
 				struct column_operators
-			{
-				template<typename T>
-					auto operator +=(T t) const -> vendor::assignment_t<Base, vendor::plus_t<Base, floating_point, vendor::wrap_operand_t<T>>>
-					{
-						using rhs = vendor::wrap_operand_t<T>;
-						static_assert(_is_valid_operand<rhs>::value, "invalid rhs assignment operand");
+				{
+					template<typename T>
+						auto operator +=(T t) const -> assignment_t<Base, plus_t<Base, floating_point, wrap_operand_t<T>>>
+						{
+							using rhs = wrap_operand_t<T>;
+							static_assert(_is_valid_operand<rhs>::value, "invalid rhs assignment operand");
 
-						return { *static_cast<const Base*>(this), { *static_cast<const Base*>(this), rhs{t} } };
-					}
+							return { *static_cast<const Base*>(this), { *static_cast<const Base*>(this), rhs{t} } };
+						}
 
-				template<typename T>
-					auto operator -=(T t) const -> vendor::assignment_t<Base, vendor::minus_t<Base, floating_point, vendor::wrap_operand_t<T>>>
-					{
-						using rhs = vendor::wrap_operand_t<T>;
-						static_assert(_is_valid_operand<rhs>::value, "invalid rhs assignment operand");
+					template<typename T>
+						auto operator -=(T t) const -> assignment_t<Base, minus_t<Base, floating_point, wrap_operand_t<T>>>
+						{
+							using rhs = wrap_operand_t<T>;
+							static_assert(_is_valid_operand<rhs>::value, "invalid rhs assignment operand");
 
-						return { *static_cast<const Base*>(this), { *static_cast<const Base*>(this), rhs{t} } };
-					}
+							return { *static_cast<const Base*>(this), { *static_cast<const Base*>(this), rhs{t} } };
+						}
 
-				template<typename T>
-					auto operator /=(T t) const -> vendor::assignment_t<Base, vendor::divides_t<Base, vendor::wrap_operand_t<T>>>
-					{
-						using rhs = vendor::wrap_operand_t<T>;
-						static_assert(_is_valid_operand<rhs>::value, "invalid rhs assignment operand");
+					template<typename T>
+						auto operator /=(T t) const -> assignment_t<Base, divides_t<Base, wrap_operand_t<T>>>
+						{
+							using rhs = wrap_operand_t<T>;
+							static_assert(_is_valid_operand<rhs>::value, "invalid rhs assignment operand");
 
-						return { *static_cast<const Base*>(this), { *static_cast<const Base*>(this), rhs{t} } };
-					}
+							return { *static_cast<const Base*>(this), { *static_cast<const Base*>(this), rhs{t} } };
+						}
 
-				template<typename T>
-					auto operator *=(T t) const -> vendor::assignment_t<Base, vendor::multiplies_t<Base, floating_point, vendor::wrap_operand_t<T>>>
-					{
-						using rhs = vendor::wrap_operand_t<T>;
-						static_assert(_is_valid_operand<rhs>::value, "invalid rhs assignment operand");
+					template<typename T>
+						auto operator *=(T t) const -> assignment_t<Base, multiplies_t<Base, floating_point, wrap_operand_t<T>>>
+						{
+							using rhs = wrap_operand_t<T>;
+							static_assert(_is_valid_operand<rhs>::value, "invalid rhs assignment operand");
 
-						return { *static_cast<const Base*>(this), { *static_cast<const Base*>(this), rhs{t} } };
-					}
-			};
+							return { *static_cast<const Base*>(this), { *static_cast<const Base*>(this), rhs{t} } };
+						}
+				};
 		};
 
 		template<typename Db, bool TrivialIsNull>
-		inline std::ostream& operator<<(std::ostream& os, const floating_point::_result_entry_t<Db, TrivialIsNull>& e)
-		{
-			return os << e.value();
-		}
+			inline std::ostream& operator<<(std::ostream& os, const floating_point::_result_entry_t<Db, TrivialIsNull>& e)
+			{
+				return os << e.value();
+			}
 	}
 
 	using floating_point = detail::floating_point;

include/sqlpp11/from.h

@@ -0,0 +1,225 @@
+/*
+ * Copyright (c) 2013-2014, Roland Bock
+ * All rights reserved.
+ * 
+ * Redistribution and use in source and binary forms, with or without modification,
+ * are permitted provided that the following conditions are met:
+ * 
+ *   Redistributions of source code must retain the above copyright notice, this
+ *   list of conditions and the following disclaimer.
+ * 
+ *   Redistributions in binary form must reproduce the above copyright notice, this
+ *   list of conditions and the following disclaimer in the documentation and/or
+ *   other materials provided with the distribution.
+ * 
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR
+ * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+ * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef SQLPP_FROM_H
+#define SQLPP_FROM_H
+
+#include <sqlpp11/type_traits.h>
+#include <sqlpp11/no_data.h>
+#include <sqlpp11/interpretable_list.h>
+#include <sqlpp11/interpret_tuple.h>
+#include <sqlpp11/detail/logic.h>
+#include <sqlpp11/detail/sum.h>
+#include <sqlpp11/policy_update.h>
+
+namespace sqlpp
+{
+	// FROM DATA
+	template<typename Database, typename... Tables>
+		struct from_data_t
+		{
+			from_data_t(Tables... tables):
+				_tables(tables...)
+			{}
+
+			from_data_t(const from_data_t&) = default;
+			from_data_t(from_data_t&&) = default;
+			from_data_t& operator=(const from_data_t&) = default;
+			from_data_t& operator=(from_data_t&&) = default;
+			~from_data_t() = default;
+
+			std::tuple<Tables...> _tables;
+			interpretable_list_t<Database> _dynamic_tables;
+		};
+
+	// FROM
+	template<typename Database, typename... Tables>
+		struct from_t
+		{
+			using _traits = make_traits<no_value_t, ::sqlpp::tag::from>;
+			using _recursive_traits = make_recursive_traits<Tables...>;
+			using _is_dynamic = is_database<Database>;
+
+			// Data
+			using _data_t = from_data_t<Database, Tables...>;
+
+			// Member implementation with data and methods
+			template<typename Policies>
+				struct _impl_t
+				{
+					template<typename Table>
+						void add(Table table)
+						{
+							static_assert(_is_dynamic::value, "from::add() must not be called for static from()");
+							static_assert(is_table_t<Table>::value, "invalid table argument in from::add()");
+							using _known_tables = detail::make_joined_set_t<provided_tables_of<Tables>...>; // Hint: Joins contain more than one table
+							using _known_table_names = detail::transform_set_t<name_of, _known_tables>;
+							static_assert(not detail::is_element_of<typename Table::_name_t, _known_table_names>::value, "Must not use the same table name twice in from()");
+
+							using ok = ::sqlpp::detail::all_t<_is_dynamic::value, is_table_t<Table>::value>;
+
+							_add_impl(table, ok()); // dispatch to prevent compile messages after the static_assert
+						}
+
+				private:
+					template<typename Table>
+						void _add_impl(Table table, const std::true_type&)
+						{
+							return _data._dynamic_tables.emplace_back(table);
+						}
+
+					template<typename Table>
+						void _add_impl(Table table, const std::false_type&);
+
+				public:
+					_data_t _data;
+				};
+
+			// Member template for adding the named member to a statement
+			template<typename Policies>
+				struct _member_t
+				{
+					using _data_t = from_data_t<Database, Tables...>;
+
+					_impl_t<Policies> from;
+					_impl_t<Policies>& operator()() { return from; }
+					const _impl_t<Policies>& operator()() const { return from; }
+
+					template<typename T>
+						static auto _get_member(T t) -> decltype(t.from)
+						{
+							return t.from;
+						}
+				};
+
+			// Additional methods for the statement
+			template<typename Policies>
+				struct _methods_t
+				{
+					static void _check_consistency() {}
+				};
+		};
+
+	struct no_from_t
+	{
+		using _traits = make_traits<no_value_t, ::sqlpp::tag::noop>;
+		using _recursive_traits = make_recursive_traits<>;
+
+		// Data
+		using _data_t = no_data_t;
+
+		// Member implementation with data and methods
+		template<typename Policies>
+			struct _impl_t
+			{
+				_data_t _data;
+			};
+
+		// Member template for adding the named member to a statement
+		template<typename Policies>
+			struct _member_t
+			{
+				using _data_t = no_data_t;
+
+				_impl_t<Policies> no_from;
+				_impl_t<Policies>& operator()() { return no_from; }
+				const _impl_t<Policies>& operator()() const { return no_from; }
+
+				template<typename T>
+					static auto _get_member(T t) -> decltype(t.no_from)
+					{
+						return t.no_from;
+					}
+			};
+
+		// Additional methods for the statement
+		template<typename Policies>
+			struct _methods_t
+			{
+				using _database_t = typename Policies::_database_t;
+				template<typename T>
+					using _new_statement_t = typename Policies::template _new_statement_t<no_from_t, T>;
+
+				static void _check_consistency() {}
+
+				template<typename... Tables>
+					auto from(Tables... tables)
+					-> _new_statement_t<from_t<void, Tables...>>
+					{
+						static_assert(sizeof...(Tables), "at least one table or join argument required in from()");
+						return _from_impl<void>(tables...);
+					}
+
+				template<typename... Tables>
+					auto dynamic_from(Tables... tables)
+					-> _new_statement_t<from_t<_database_t, Tables...>>
+					{
+						static_assert(not std::is_same<_database_t, void>::value, "dynamic_from must not be called in a static statement");
+						return _from_impl<_database_t>(tables...);
+					}
+
+			private:
+				template<typename Database, typename... Tables>
+					auto _from_impl(Tables... tables)
+					-> _new_statement_t<from_t<Database, Tables...>>
+					{
+						static_assert(::sqlpp::detail::all_t<is_table_t<Tables>::value...>::value, "at least one argument is not a table or join in from()");
+						static_assert(required_tables_of<from_t<Database, Tables...>>::size::value == 0, "at least one table depends on another table");
+
+						static constexpr std::size_t _number_of_tables = detail::sum(provided_tables_of<Tables>::size::value...);
+						using _unique_tables = detail::make_joined_set_t<provided_tables_of<Tables>...>;
+						using _unique_table_names = detail::transform_set_t<name_of, _unique_tables>;
+						static_assert(_number_of_tables == _unique_tables::size::value, "at least one duplicate table detected in from()");
+						static_assert(_number_of_tables == _unique_table_names::size::value, "at least one duplicate table name detected in from()");
+
+						return { *static_cast<typename Policies::_statement_t*>(this), from_data_t<Database, Tables...>{tables...} };
+					}
+
+			};
+	};
+
+	// Interpreters
+	template<typename Context, typename Database, typename... Tables>
+		struct serializer_t<Context, from_data_t<Database, Tables...>>
+		{
+			using T = from_data_t<Database, Tables...>;
+
+			static Context& _(const T& t, Context& context)
+			{
+				if (sizeof...(Tables) == 0 and t._dynamic_tables.empty())
+					return context;
+				context << " FROM ";
+				interpret_tuple(t._tables, ',', context);
+				if (sizeof...(Tables) and not t._dynamic_tables.empty())
+					context << ',';
+				interpret_list(t._dynamic_tables, ',', context);
+				return context;
+			}
+		};
+
+}
+
+#endif

include/sqlpp11/functions.h

@@ -30,9 +30,9 @@
 #include <sqlpp11/parameter.h>
 #include <sqlpp11/parameter_list.h>
 #include <sqlpp11/column_types.h>
-#include <sqlpp11/vendor/in.h>
-#include <sqlpp11/vendor/is_null.h>
-#include <sqlpp11/vendor/value_type.h>
+#include <sqlpp11/in.h>
+#include <sqlpp11/is_null.h>
+#include <sqlpp11/value_type.h>
 #include <sqlpp11/exists.h>
 #include <sqlpp11/any.h>
 #include <sqlpp11/some.h>
@@ -46,18 +46,18 @@
 namespace sqlpp
 {
 	template<typename T>
-		auto value(T t) -> vendor::wrap_operand_t<T>
+		auto value(T t) -> wrap_operand_t<T>
 		{
-			using _table_set = ::sqlpp::detail::type_set<>;
-			static_assert(not is_value_t<T>::value, "value() is to be called with non-sql-type like int, or string");
+			static_assert(is_wrapped_value_t<wrap_operand_t<T>>::value, "value() is to be called with non-sql-type like int, or string");
 			return { t };
 		}
 
 	template<typename ValueType> // Csaba Csoma suggests: unsafe_sql instead of verbatim
-	struct verbatim_t: public ValueType::template expression_operators<verbatim_t<ValueType>>
+		struct verbatim_t: public ValueType::template expression_operators<verbatim_t<ValueType>>,
+		public alias_operators<verbatim_t<ValueType>>
 	{
-		using _value_type = ValueType;
-		using _table_set = ::sqlpp::detail::type_set<>;
+		using _traits = make_traits<ValueType, ::sqlpp::tag::expression>;
+		using _recursive_traits = make_recursive_traits<>;
 
 		verbatim_t(std::string verbatim): _verbatim(verbatim) {}
 		verbatim_t(const verbatim_t&) = default;
@@ -69,20 +69,17 @@ namespace sqlpp
 		std::string _verbatim;
 	};
 
-	namespace vendor
-	{
-		template<typename Context, typename ValueType>
-			struct serializer_t<Context, verbatim_t<ValueType>>
-			{
-				using T = verbatim_t<ValueType>;
+	template<typename Context, typename ValueType>
+		struct serializer_t<Context, verbatim_t<ValueType>>
+		{
+			using T = verbatim_t<ValueType>;
 
-				static Context& _(const T& t, Context& context)
-				{
-					context << t._verbatim;
-					return context;
-				}
-			};
-	}
+			static Context& _(const T& t, Context& context)
+			{
+				context << t._verbatim;
+				return context;
+			}
+		};
 
 	template<typename ValueType, typename StringType>
 		auto verbatim(StringType s) -> verbatim_t<ValueType>
@@ -91,7 +88,7 @@ namespace sqlpp
 		}
 
 	template<typename Expression, typename Context>
-		auto flatten(const Expression& exp, const Context& context) -> verbatim_t<typename Expression::_value_type::_base_value_type>
+		auto flatten(const Expression& exp, const Context& context) -> verbatim_t<value_type_of<Expression>>
 		{
 			static_assert(not make_parameter_list_t<Expression>::type::size::value, "parameters not supported in flattened expressions");
 			context.clear();
@@ -102,9 +99,10 @@ namespace sqlpp
 	template<typename Container>
 		struct value_list_t // to be used in .in() method
 		{
+			using _traits = make_traits<value_type_t<typename Container::value_type>, ::sqlpp::tag::expression>;
+			using _recursive_traits = make_recursive_traits<>;
+
 			using _container_t = Container;
-			using _table_set = ::sqlpp::detail::type_set<>;// FIXME: Could it be something else?
-			using _value_type = vendor::value_type_t<typename _container_t::value_type>;
 
 			value_list_t(_container_t container):
 				_container(container)
@@ -119,34 +117,31 @@ namespace sqlpp
 			_container_t _container;
 		};
 
-	namespace vendor
-	{
-		template<typename Context, typename Container>
-			struct serializer_t<Context, value_list_t<Container>>
+	template<typename Context, typename Container>
+		struct serializer_t<Context, value_list_t<Container>>
+		{
+			using T = value_list_t<Container>;
+
+			static Context& _(const T& t, Context& context)
 			{
-				using T = value_list_t<Container>;
-
-				static Context& _(const T& t, Context& context)
+				bool first = true;
+				for (const auto& entry: t._container)
 				{
-					bool first = true;
-					for (const auto& entry: t._container)
-					{
-						if (first)
-							first = false;
-						else
-							context << ',';
+					if (first)
+						first = false;
+					else
+						context << ',';
 
-						serialize(value(entry), context);
-					}
-					return context;
+					serialize(value(entry), context);
 				}
-			};
-	}
+				return context;
+			}
+		};
 
 	template<typename Container>
 		auto value_list(Container c) -> value_list_t<Container>
 		{
-			static_assert(not is_value_t<typename Container::value_type>::value, "value_list() is to be called with a container of non-sql-type like std::vector<int>, or std::list(string)");
+			static_assert(is_wrapped_value_t<wrap_operand_t<typename Container::value_type>>::value, "value_list() is to be called with a container of non-sql-type like std::vector<int>, or std::list(string)");
 			return { c };
 		}
 

include/sqlpp11/group_by.h

@@ -0,0 +1,214 @@
+/*
+ * Copyright (c) 2013-2014, Roland Bock
+ * All rights reserved.
+ * 
+ * Redistribution and use in source and binary forms, with or without modification,
+ * are permitted provided that the following conditions are met:
+ * 
+ *   Redistributions of source code must retain the above copyright notice, this
+ *   list of conditions and the following disclaimer.
+ * 
+ *   Redistributions in binary form must reproduce the above copyright notice, this
+ *   list of conditions and the following disclaimer in the documentation and/or
+ *   other materials provided with the distribution.
+ * 
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR
+ * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+ * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef SQLPP_GROUP_BY_H
+#define SQLPP_GROUP_BY_H
+
+#include <tuple>
+#include <sqlpp11/type_traits.h>
+#include <sqlpp11/expression.h>
+#include <sqlpp11/interpret_tuple.h>
+#include <sqlpp11/interpretable_list.h>
+#include <sqlpp11/policy_update.h>
+#include <sqlpp11/detail/logic.h>
+
+namespace sqlpp
+{
+	// GROUP BY DATA
+	template<typename Database, typename... Expressions>
+		struct group_by_data_t
+		{
+			group_by_data_t(Expressions... expressions):
+				_expressions(expressions...)
+			{}
+
+			group_by_data_t(const group_by_data_t&) = default;
+			group_by_data_t(group_by_data_t&&) = default;
+			group_by_data_t& operator=(const group_by_data_t&) = default;
+			group_by_data_t& operator=(group_by_data_t&&) = default;
+			~group_by_data_t() = default;
+
+			std::tuple<Expressions...> _expressions;
+			interpretable_list_t<Database> _dynamic_expressions;
+		};
+
+	// GROUP BY
+	template<typename Database, typename... Expressions>
+		struct group_by_t
+		{
+			using _traits = make_traits<no_value_t, ::sqlpp::tag::group_by>;
+			using _recursive_traits = make_recursive_traits<Expressions...>;
+
+			using _is_dynamic = is_database<Database>;
+
+			static_assert(_is_dynamic::value or sizeof...(Expressions), "at least one expression (e.g. a column) required in group_by()");
+
+			static_assert(not ::sqlpp::detail::has_duplicates<Expressions...>::value, "at least one duplicate argument detected in group_by()");
+
+			static_assert(::sqlpp::detail::all_t<is_expression_t<Expressions>::value...>::value, "at least one argument is not an expression in group_by()");
+
+			// Data
+			using _data_t = group_by_data_t<Database, Expressions...>;
+
+			// Member implementation with data and methods
+			template<typename Policies>
+				struct _impl_t
+				{
+					template<typename Expression>
+						void add_ntc(Expression expression)
+						{
+							add<Expression, std::false_type>(expression);
+						}
+
+					template<typename Expression, typename TableCheckRequired = std::true_type>
+						void add(Expression expression)
+						{
+							static_assert(_is_dynamic::value, "add() must not be called for static group_by");
+							static_assert(is_expression_t<Expression>::value, "invalid expression argument in group_by::add()");
+							static_assert(TableCheckRequired::value or Policies::template _no_unknown_tables<Expression>::value, "expression uses tables unknown to this statement in group_by::add()");
+
+							using ok = ::sqlpp::detail::all_t<_is_dynamic::value, is_expression_t<Expression>::value>;
+
+							_add_impl(expression, ok()); // dispatch to prevent compile messages after the static_assert
+						}
+
+				private:
+					template<typename Expression>
+						void _add_impl(Expression expression, const std::true_type&)
+						{
+							return _data._dynamic_expressions.emplace_back(expression);
+						}
+
+					template<typename Expression>
+						void _add_impl(Expression expression, const std::false_type&);
+				public:
+					_data_t _data;
+				};
+
+			// Member template for adding the named member to a statement
+			template<typename Policies>
+				struct _member_t
+				{
+					using _data_t = group_by_data_t<Database, Expressions...>;
+
+					_impl_t<Policies> group_by;
+					_impl_t<Policies>& operator()() { return group_by; }
+					const _impl_t<Policies>& operator()() const { return group_by; }
+
+					template<typename T>
+						static auto _get_member(T t) -> decltype(t.group_by)
+						{
+							return t.group_by;
+						}
+				};
+
+			template<typename Policies>
+				struct _methods_t
+				{
+					static void _check_consistency() {}
+				};
+		};
+
+	// NO GROUP BY YET
+	struct no_group_by_t
+	{
+		using _traits = make_traits<no_value_t, ::sqlpp::tag::noop>;
+		using _recursive_traits = make_recursive_traits<>;
+
+		// Data
+		using _data_t = no_data_t;
+
+		// Member implementation with data and methods
+		template<typename Policies>
+			struct _impl_t
+			{
+				_data_t _data;
+			};
+
+		// Member template for adding the named member to a statement
+		template<typename Policies>
+			struct _member_t
+			{
+				using _data_t = no_data_t;
+
+				_impl_t<Policies> no_group_by;
+				_impl_t<Policies>& operator()() { return no_group_by; }
+				const _impl_t<Policies>& operator()() const { return no_group_by; }
+
+				template<typename T>
+					static auto _get_member(T t) -> decltype(t.no_group_by)
+					{
+						return t.no_group_by;
+					}
+			};
+
+		template<typename Policies>
+			struct _methods_t
+			{
+				using _database_t = typename Policies::_database_t;
+				template<typename T>
+					using _new_statement_t = typename Policies::template _new_statement_t<no_group_by_t, T>;
+
+				static void _check_consistency() {}
+
+				template<typename... Args>
+					auto group_by(Args... args)
+					-> _new_statement_t<group_by_t<void, Args...>>
+					{
+						return { *static_cast<typename Policies::_statement_t*>(this), group_by_data_t<void, Args...>{args...} };
+					}
+
+				template<typename... Args>
+					auto dynamic_group_by(Args... args)
+					-> _new_statement_t<group_by_t<_database_t, Args...>>
+					{
+						static_assert(not std::is_same<_database_t, void>::value, "dynamic_group_by must not be called in a static statement");
+						return { *static_cast<typename Policies::_statement_t*>(this), group_by_data_t<_database_t, Args...>{args...} };
+					}
+			};
+	};
+
+	// Interpreters
+	template<typename Context, typename Database, typename... Expressions>
+		struct serializer_t<Context, group_by_data_t<Database, Expressions...>>
+		{
+			using T = group_by_data_t<Database, Expressions...>;
+
+			static Context& _(const T& t, Context& context)
+			{
+				if (sizeof...(Expressions) == 0 and t._dynamic_expressions.empty())
+					return context;
+				context << " GROUP BY ";
+				interpret_tuple(t._expressions, ',', context);
+				if (sizeof...(Expressions) and not t._dynamic_expressions.empty())
+					context << ',';
+				interpret_list(t._dynamic_expressions, ',', context);
+				return context;
+			}
+		};
+}
+
+#endif

include/sqlpp11/having.h

@@ -0,0 +1,212 @@
+/*
+ * Copyright (c) 2013-2014, Roland Bock
+ * All rights reserved.
+ * 
+ * Redistribution and use in source and binary forms, with or without modification,
+ * are permitted provided that the following conditions are met:
+ * 
+ *   Redistributions of source code must retain the above copyright notice, this
+ *   list of conditions and the following disclaimer.
+ * 
+ *   Redistributions in binary form must reproduce the above copyright notice, this
+ *   list of conditions and the following disclaimer in the documentation and/or
+ *   other materials provided with the distribution.
+ * 
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR
+ * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+ * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef SQLPP_HAVING_H
+#define SQLPP_HAVING_H
+
+#include <sqlpp11/type_traits.h>
+#include <sqlpp11/expression.h>
+#include <sqlpp11/interpret_tuple.h>
+#include <sqlpp11/interpretable_list.h>
+#include <sqlpp11/policy_update.h>
+#include <sqlpp11/detail/logic.h>
+
+namespace sqlpp
+{
+	// HAVING DATA
+	template<typename Database, typename... Expressions>
+		struct having_data_t
+		{
+			having_data_t(Expressions... expressions):
+				_expressions(expressions...)
+			{}
+
+			having_data_t(const having_data_t&) = default;
+			having_data_t(having_data_t&&) = default;
+			having_data_t& operator=(const having_data_t&) = default;
+			having_data_t& operator=(having_data_t&&) = default;
+			~having_data_t() = default;
+
+			std::tuple<Expressions...> _expressions;
+			interpretable_list_t<Database> _dynamic_expressions;
+		};
+
+	// HAVING
+	template<typename Database, typename... Expressions>
+		struct having_t
+		{
+			using _traits = make_traits<no_value_t, ::sqlpp::tag::having>;
+			using _recursive_traits = make_recursive_traits<Expressions...>;
+
+			using _is_dynamic = is_database<Database>;
+
+			static_assert(_is_dynamic::value or sizeof...(Expressions), "at least one expression argument required in having()");
+			static_assert(::sqlpp::detail::all_t<is_expression_t<Expressions>::value...>::value, "at least one argument is not an expression in having()");
+
+			// Data
+			using _data_t = having_data_t<Database, Expressions...>;
+
+			// Member implementation with data and methods
+			template <typename Policies>
+				struct _impl_t
+				{
+					template<typename Expression>
+						void add_ntc(Expression expression)
+						{
+							add<Expression, std::false_type>(expression);
+						}
+
+					template<typename Expression, typename TableCheckRequired = std::true_type>
+						void add(Expression expression)
+						{
+							static_assert(_is_dynamic::value, "having::add() can only be called for dynamic_having");
+							static_assert(is_expression_t<Expression>::value, "invalid expression argument in having::add()");
+							static_assert(not TableCheckRequired::value or Policies::template _no_unknown_tables<Expression>::value, "expression uses tables unknown to this statement in having::add()");
+
+							using ok = ::sqlpp::detail::all_t<_is_dynamic::value, is_expression_t<Expression>::value>;
+
+							_add_impl(expression, ok()); // dispatch to prevent compile messages after the static_assert
+						}
+
+				private:
+					template<typename Expression>
+						void _add_impl(Expression expression, const std::true_type&)
+						{
+							return _data._dynamic_expressions.emplace_back(expression);
+						}
+
+					template<typename Expression>
+						void _add_impl(Expression expression, const std::false_type&);
+
+				public:
+					_data_t _data;
+				};
+
+			// Member template for adding the named member to a statement
+			template<typename Policies>
+				struct _member_t
+				{
+					using _data_t = having_data_t<Database, Expressions...>;
+
+					_impl_t<Policies> having;
+					_impl_t<Policies>& operator()() { return having; }
+					const _impl_t<Policies>& operator()() const { return having; }
+
+					template<typename T>
+						static auto _get_member(T t) -> decltype(t.having)
+						{
+							return t.having;
+						}
+				};
+
+			// Additional methods for the statement
+			template<typename Policies>
+				struct _methods_t
+				{
+					static void _check_consistency() {}
+				};
+		};
+
+	// NO HAVING YET
+	struct no_having_t
+	{
+		using _traits = make_traits<no_value_t, ::sqlpp::tag::noop>;
+		using _recursive_traits = make_recursive_traits<>;
+
+		// Data
+		using _data_t = no_data_t;
+
+		// Member implementation with data and methods
+		template<typename Policies>
+			struct _impl_t
+			{
+				_data_t _data;
+			};
+
+		// Member template for adding the named member to a statement
+		template<typename Policies>
+			struct _member_t
+			{
+				using _data_t = no_data_t;
+
+				_impl_t<Policies> no_having;
+				_impl_t<Policies>& operator()() { return no_having; }
+				const _impl_t<Policies>& operator()() const { return no_having; }
+
+				template<typename T>
+					static auto _get_member(T t) -> decltype(t.no_having)
+					{
+						return t.no_having;
+					}
+			};
+
+		template<typename Policies>
+			struct _methods_t
+			{
+				using _database_t = typename Policies::_database_t;
+				template<typename T>
+					using _new_statement_t = typename Policies::template _new_statement_t<no_having_t, T>;
+
+				static void _check_consistency() {}
+
+				template<typename... Args>
+					auto having(Args... args)
+					-> _new_statement_t<having_t<void, Args...>>
+					{
+						return { *static_cast<typename Policies::_statement_t*>(this), having_data_t<void, Args...>{args...} };
+					}
+
+				template<typename... Args>
+					auto dynamic_having(Args... args)
+					-> _new_statement_t<having_t<_database_t, Args...>>
+					{
+						static_assert(not std::is_same<_database_t, void>::value, "dynamic_having must not be called in a static statement");
+						return { *static_cast<typename Policies::_statement_t*>(this), having_data_t<_database_t, Args...>{args...} };
+					}
+			};
+	};
+
+	// Interpreters
+	template<typename Context, typename Database, typename... Expressions>
+		struct serializer_t<Context, having_data_t<Database, Expressions...>>
+		{
+			using T = having_data_t<Database, Expressions...>;
+
+			static Context& _(const T& t, Context& context)
+			{
+				if (sizeof...(Expressions) == 0 and t._dynamic_expressions.empty())
+					return context;
+				context << " HAVING ";
+				interpret_tuple(t._expressions, " AND ", context);
+				if (sizeof...(Expressions) and not t._dynamic_expressions.empty())
+					context << " AND ";
+				interpret_list(t._dynamic_expressions, " AND ", context);
+				return context;
+			}
+		};
+}
+
+#endif

include/sqlpp11/in.h

@@ -29,65 +29,60 @@
 
 #include <sqlpp11/type_traits.h>
 #include <sqlpp11/boolean.h>
-#include <sqlpp11/vendor/in_fwd.h>
+#include <sqlpp11/in_fwd.h>
 #include <sqlpp11/detail/type_set.h>
 
 namespace sqlpp
 {
-	namespace vendor
+	template<bool NotInverted, typename Operand, typename... Args>
+		struct in_t: public boolean::template expression_operators<in_t<NotInverted, Operand, Args...>>,
+		public alias_operators<in_t<NotInverted, Operand, Args...>>
 	{
-		template<bool NotInverted, typename Operand, typename... Args>
-			struct in_t: public boolean::template expression_operators<in_t<NotInverted, Operand, Args...>>
+		using _traits = make_traits<boolean, ::sqlpp::tag::expression, ::sqlpp::tag::named_expression>;
+		using _recursive_traits = make_recursive_traits<Operand, Args...>;
+
+		static constexpr bool _inverted = not NotInverted;
+		static_assert(sizeof...(Args) > 0, "in() requires at least one argument");
+
+		struct _name_t
 		{
-			static constexpr bool _inverted = not NotInverted;
-			static_assert(sizeof...(Args) > 0, "in() requires at least one argument");
-
-			struct _value_type: public boolean
-			{
-				using _is_named_expression = std::true_type;
-			};
-
-			struct _name_t
-			{
-				static constexpr const char* _get_name() { return _inverted ? "NOT IN" : "IN"; }
-				template<typename T>
-					struct _member_t
-					{
-						T in;
-					};
-			};
-			using _table_set = typename ::sqlpp::detail::make_joined_set<typename Operand::_table_set, typename Args::_table_set...>::type;
-
-			in_t(Operand operand, Args... args):
-				_operand(operand),
-				_args(args...)
-			{}
-
-			in_t(const in_t&) = default;
-			in_t(in_t&&) = default;
-			in_t& operator=(const in_t&) = default;
-			in_t& operator=(in_t&&) = default;
-			~in_t() = default;
-
-			Operand _operand;
-			std::tuple<Args...> _args;
+			static constexpr const char* _get_name() { return _inverted ? "NOT IN" : "IN"; }
+			template<typename T>
+				struct _member_t
+				{
+					T in;
+				};
 		};
 
-		template<typename Context, bool NotInverted, typename Operand, typename... Args>
-			struct serializer_t<Context, vendor::in_t<NotInverted, Operand, Args...>>
-			{
-				using T = vendor::in_t<NotInverted, Operand, Args...>;
+		in_t(Operand operand, Args... args):
+			_operand(operand),
+			_args(args...)
+		{}
 
-				static Context& _(const T& t, Context& context)
-				{
-					serialize(t._operand, context);
-					context << (t._inverted ? " NOT IN(" : " IN(");
-					interpret_tuple(t._args, ',', context);
-					context << ')';
-					return context;
-				}
-			};
-	}
+		in_t(const in_t&) = default;
+		in_t(in_t&&) = default;
+		in_t& operator=(const in_t&) = default;
+		in_t& operator=(in_t&&) = default;
+		~in_t() = default;
+
+		Operand _operand;
+		std::tuple<Args...> _args;
+	};
+
+	template<typename Context, bool NotInverted, typename Operand, typename... Args>
+		struct serializer_t<Context, in_t<NotInverted, Operand, Args...>>
+		{
+			using T = in_t<NotInverted, Operand, Args...>;
+
+			static Context& _(const T& t, Context& context)
+			{
+				serialize(t._operand, context);
+				context << (t._inverted ? " NOT IN(" : " IN(");
+				interpret_tuple(t._args, ',', context);
+				context << ')';
+				return context;
+			}
+		};
 
 }
 

include/sqlpp11/in_fwd.h

@@ -29,11 +29,8 @@
 
 namespace sqlpp
 {
-	namespace vendor
-	{
-		template<bool NotInverted, typename Operand, typename... Args>
+	template<bool NotInverted, typename Operand, typename... Args>
 		struct in_t;
-	}
 
 }
 

include/sqlpp11/insert.h

@@ -27,172 +27,99 @@
 #ifndef SQLPP_INSERT_H
 #define SQLPP_INSERT_H
 
+#include <sqlpp11/statement.h>
 #include <sqlpp11/type_traits.h>
 #include <sqlpp11/parameter_list.h>
 #include <sqlpp11/prepared_insert.h>
 #include <sqlpp11/default_value.h>
-#include <sqlpp11/vendor/noop.h>
-#include <sqlpp11/vendor/single_table.h>
-#include <sqlpp11/vendor/insert_value_list.h>
-#include <sqlpp11/vendor/policy_update.h>
-#include <sqlpp11/detail/arg_selector.h>
+#include <sqlpp11/noop.h>
+#include <sqlpp11/into.h>
+#include <sqlpp11/insert_value_list.h>
 
 namespace sqlpp
 {
-	template<typename Db,
-			typename... Policies
-			>
-		struct insert_t;
+	struct insert_name_t {};
 
-	namespace detail
+	struct insert_t: public statement_name_t<insert_name_t>
 	{
-		template<typename Db,
-				typename Table = vendor::no_single_table_t,
-				typename InsertValueList = vendor::no_insert_value_list_t
-				>
-			struct insert_policies_t
+		using _traits = make_traits<no_value_t, tag::return_value>;
+		struct _name_t {};
+
+		template<typename Policies>
+			struct _result_methods_t
 			{
-				using _database_t = Db;
-				using _table_t = Table;
-				using _insert_value_list_t = InsertValueList;
+				using _statement_t = typename Policies::_statement_t;
 
-				using _statement_t = insert_t<Db, Table, InsertValueList>;
+				const _statement_t& _get_statement() const
+				{
+					return static_cast<const _statement_t&>(*this);
+				}
 
-				struct _methods_t:
-					public _insert_value_list_t::template _methods_t<insert_policies_t>
-				{};
-
-				template<typename Needle, typename Replacement, typename... Policies>
-					struct _policies_insert_t
+				template<typename Db>
+					auto _run(Db& db) const -> decltype(db.insert(this->_get_statement()))
 					{
-						using type =  insert_t<Db, vendor::policy_update_t<Policies, Needle, Replacement>...>;
-					};
+						_statement_t::_check_consistency();
 
-				template<typename Needle, typename Replacement>
-					using _new_statement_t = typename _policies_insert_t<Needle, Replacement, Table, InsertValueList>::type;
+						static_assert(_statement_t::_get_static_no_of_parameters() == 0, "cannot run insert directly with parameters, use prepare instead");
+						return db.insert(_get_statement());
+					}
 
-				using _table_set = typename _table_t::_table_set;
+					 template<typename Db>
+					 auto _prepare(Db& db) const
+					 -> prepared_insert_t<Db, _statement_t>
+					 {
+						 _statement_t::_check_consistency();
 
-				using _known_tables = detail::make_joined_set_t<typename _table_t::_table_set>;
-
-				template<typename Expression>
-					using _no_unknown_tables = detail::is_subset_of<typename Expression::_table_set, _known_tables>;
+						 return {{}, db.prepare_insert(_get_statement())};
+					 }
 			};
-	}
+	};
 
-	// INSERT
-	template<typename Db,
-			typename... Policies
-			>
-		struct insert_t:
-			public detail::insert_policies_t<Db, Policies...>::_methods_t
+	template<typename Context>
+		struct serializer_t<Context, insert_name_t>
 		{
-			using _policies_t = typename detail::insert_policies_t<Db, Policies...>;
-			using _database_t = typename _policies_t::_database_t;
-			using _table_t = typename _policies_t::_table_t;
-			using _insert_value_list_t = typename _policies_t::_insert_value_list_t;
+			using T = insert_name_t;
 
-			using _is_dynamic = typename std::conditional<std::is_same<_database_t, void>::value, std::false_type, std::true_type>::type;
-
-			using _parameter_tuple_t = std::tuple<Policies...>;
-			using _parameter_list_t = typename make_parameter_list_t<insert_t>::type;
-
-			static_assert(::sqlpp::detail::is_superset_of<typename _table_t::_table_set, typename _insert_value_list_t::_table_set>::value, "columns do not match the table they are to be inserted into");
-
-			// Constructors
-			insert_t()
-			{}
-
-			template<typename Statement, typename T>
-				insert_t(Statement s, T t):
-					_table(detail::arg_selector<_table_t>::_(s._table, t)),
-					_insert_value_list(detail::arg_selector<_insert_value_list_t>::_(s._insert_value_list, t))
-			{}
-
-			insert_t(const insert_t&) = default;
-			insert_t(insert_t&&) = default;
-			insert_t& operator=(const insert_t&) = default;
-			insert_t& operator=(insert_t&&) = default;
-			~insert_t() = default;
-
-			// run and prepare
-			static constexpr size_t _get_static_no_of_parameters()
+			static Context& _(const T& t, Context& context)
 			{
-				return _parameter_list_t::size::value;
+				context << "INSERT ";
+
+				return context;
 			}
-
-			size_t _get_no_of_parameters() const
-			{
-				return _parameter_list_t::size::value;
-			}
-
-			template<typename A>
-				struct is_table_subset_of_table
-				{
-					static constexpr bool value = ::sqlpp::detail::is_subset_of<typename A::_table_set, typename _table_t::_table_set>::value;
-				};
-
-			void _check_consistency() const
-			{
-				// FIXME: Read up on what is allowed/prohibited in INSERT
-			}
-
-			template<typename Database>
-				std::size_t _run(Database& db) const
-				{
-					_check_consistency();
-
-					static_assert(_get_static_no_of_parameters() == 0, "cannot run insert directly with parameters, use prepare instead");
-					return db.insert(*this);
-				}
-
-			template<typename Database>
-				auto _prepare(Database& db) const
-				-> prepared_insert_t<Database, insert_t>
-				{
-					_check_consistency();
-
-					return {{}, db.prepare_insert(*this)};
-				}
-
-			_insert_value_list_t _insert_value_list;
-			_table_t _table;
 		};
 
-	namespace vendor
-	{
-		template<typename Context, typename Database, typename... Policies>
-			struct serializer_t<Context, insert_t<Database, Policies...>>
-			{
-				using T = insert_t<Database, Policies...>;
+	template<typename Database>
+		using blank_insert_t = statement_t<Database,
+					insert_t,
+					no_into_t, 
+					no_insert_value_list_t>;
 
-				static Context& _(const T& t, Context& context)
-				{
-					context << "INSERT INTO ";
-					serialize(t._table, context);
-					serialize(t._insert_value_list, context);
-					return context;
-				}
-			};
-	}
-
-	template<typename Database, typename... Policies>
-		using make_insert_t = typename detail::insert_policies_t<Database, Policies...>::_statement_t;
+	auto insert()
+		-> blank_insert_t<void>
+		{
+			return { blank_insert_t<void>() };
+		}
 
 	template<typename Table>
 		constexpr auto insert_into(Table table)
-		-> make_insert_t<void, vendor::single_table_t<void, Table>>
+		-> decltype(blank_insert_t<void>().into(table))
 		{
-			return { make_insert_t<void>(), vendor::single_table_t<void, Table>{table} };
+			return { blank_insert_t<void>().into(table) };
+		}
+
+	template<typename Database>
+		constexpr auto  dynamic_insert(const Database&)
+		-> decltype(blank_insert_t<Database>())
+		{
+			return { blank_insert_t<Database>() };
 		}
 
 	template<typename Database, typename Table>
 		constexpr auto  dynamic_insert_into(const Database&, Table table)
-		-> make_insert_t<Database, vendor::single_table_t<void, Table>>
+		-> decltype(blank_insert_t<Database>().into(table))
 		{
-			return { make_insert_t<Database>(), vendor::single_table_t<void, Table>{table} };
+			return { blank_insert_t<Database>().into(table) };
 		}
-
 }
 
 #endif

include/sqlpp11/insert_value.h

@@ -0,0 +1,121 @@
+/*
+ * Copyright (c) 2013-2014, Roland Bock
+ * All rights reserved.
+ * 
+ * Redistribution and use in source and binary forms, with or without modification,
+ * are permitted provided that the following conditions are met:
+ * 
+ *   Redistributions of source code must retain the above copyright notice, this
+ *   list of conditions and the following disclaimer.
+ * 
+ *   Redistributions in binary form must reproduce the above copyright notice, this
+ *   list of conditions and the following disclaimer in the documentation and/or
+ *   other materials provided with the distribution.
+ * 
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR
+ * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+ * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef SQLPP_INSERT_VALUE_H
+#define SQLPP_INSERT_VALUE_H
+
+#include <sqlpp11/default_value.h>
+#include <sqlpp11/null.h>
+#include <sqlpp11/tvin.h>
+#include <sqlpp11/type_traits.h>
+#include <sqlpp11/serializer.h>
+#include <sqlpp11/detail/type_set.h>
+
+namespace sqlpp
+{
+	namespace detail
+	{
+		template<typename Type, bool>
+			struct type_if
+			{
+				using type = Type;
+			};
+
+		template<typename Type>
+			struct type_if<Type, false>
+			{
+				struct type
+				{
+					using _traits = make_traits<no_value_t, ::sqlpp::tag::noop>;
+					using _recursive_traits = make_recursive_traits<>;
+				};
+			};
+	}
+
+	template<typename Column>
+		struct insert_value_t
+		{
+			using _is_insert_value = std::true_type;
+			using _pure_value_t = typename value_type_of<Column>::_cpp_value_type;
+			using _wrapped_value_t = typename wrap_operand<_pure_value_t>::type;
+			using _tvin_t = typename detail::type_if<tvin_t<_wrapped_value_t>, can_be_null_t<Column>::value>::type; // static asserts and SFINAE do not work together
+			using _null_t = typename detail::type_if<null_t, can_be_null_t<Column>::value>::type; // static asserts and SFINAE do not work together
+
+			insert_value_t(assignment_t<Column, _wrapped_value_t> assignment):
+				_is_null(false),
+				_is_default(false),
+				_value(assignment._rhs)
+			{}
+
+			insert_value_t(assignment_t<Column, _tvin_t> assignment):
+				_is_null(assignment._rhs._is_trivial()),
+				_is_default(false),
+				_value(assignment._rhs._value)
+			{}
+
+			insert_value_t(const assignment_t<Column, _null_t>&):
+				_is_null(true),
+				_is_default(false),
+				_value()
+			{}
+
+			insert_value_t(const assignment_t<Column, ::sqlpp::default_value_t>&):
+				_is_null(false),
+				_is_default(true),
+				_value()
+			{}
+
+			insert_value_t(const insert_value_t&) = default;
+			insert_value_t(insert_value_t&&) = default;
+			insert_value_t& operator=(const insert_value_t&) = default;
+			insert_value_t& operator=(insert_value_t&&) = default;
+			~insert_value_t() = default;
+
+			bool _is_null;
+			bool _is_default;
+			_wrapped_value_t _value;
+		};
+
+	template<typename Context, typename ValueType>
+		struct serializer_t<Context, insert_value_t<ValueType>>
+		{
+			using T = insert_value_t<ValueType>;
+
+			static Context& _(const T& t, Context& context)
+			{
+				if (t._is_null)
+					context << "NULL";
+				else if (t._is_default)
+					context << "DEFAULT";
+				else
+					serialize(t._value, context);
+				return context;
+			}
+		};
+
+}
+
+#endif

include/sqlpp11/insert_value_list.h

@@ -0,0 +1,443 @@
+/*
+ * Copyright (c) 2013-2014, Roland Bock
+ * All rights reserved.
+ * 
+ * Redistribution and use in source and binary forms, with or without modification,
+ * are permitted provided that the following conditions are met:
+ * 
+ *   Redistributions of source code must retain the above copyright notice, this
+ *   list of conditions and the following disclaimer.
+ * 
+ *   Redistributions in binary form must reproduce the above copyright notice, this
+ *   list of conditions and the following disclaimer in the documentation and/or
+ *   other materials provided with the distribution.
+ * 
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR
+ * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+ * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef SQLPP_INSERT_VALUE_LIST_H
+#define SQLPP_INSERT_VALUE_LIST_H
+
+#include <sqlpp11/type_traits.h>
+#include <sqlpp11/detail/logic.h>
+#include <sqlpp11/assignment.h>
+#include <sqlpp11/interpretable_list.h>
+#include <sqlpp11/interpret_tuple.h>
+#include <sqlpp11/insert_value.h>
+#include <sqlpp11/simple_column.h>
+#include <sqlpp11/no_data.h>
+
+namespace sqlpp
+{
+	struct insert_default_values_data_t
+	{};
+
+	// COLUMN AND VALUE LIST
+	struct insert_default_values_t
+	{
+		using _traits = make_traits<no_value_t>;
+		using _recursive_traits = make_recursive_traits<>;
+
+		// Data
+		using _data_t = insert_default_values_data_t;
+
+		// Member implementation with data and methods
+		template<typename Policies>
+			struct _impl_t
+			{
+				_data_t _data;
+			};
+
+		// Member template for adding the named member to a statement
+		template<typename Policies>
+			struct _member_t
+			{
+				using _data_t = insert_default_values_data_t;
+
+				_impl_t<Policies> default_values;
+				_impl_t<Policies>& operator()() { return default_values; }
+				const _impl_t<Policies>& operator()() const { return default_values; }
+
+				template<typename T>
+					static auto _get_member(T t) -> decltype(t.default_values)
+					{
+						return t.default_values;
+					}
+			};
+
+		template<typename Policies>
+			struct _methods_t
+			{
+				static void _check_consistency() {}
+			};
+	}; 
+
+	template<typename Database, typename... Assignments>
+		struct insert_list_data_t
+		{
+			insert_list_data_t(Assignments... assignments):
+				_assignments(assignments...),
+				_columns({assignments._lhs}...),
+				_values(assignments._rhs...)
+				{}
+
+			insert_list_data_t(const insert_list_data_t&) = default;
+			insert_list_data_t(insert_list_data_t&&) = default;
+			insert_list_data_t& operator=(const insert_list_data_t&) = default;
+			insert_list_data_t& operator=(insert_list_data_t&&) = default;
+			~insert_list_data_t() = default;
+
+			std::tuple<Assignments...> _assignments; // FIXME: Need to replace _columns and _values by _assignments (connector-container requires assignments)
+			std::tuple<simple_column_t<typename Assignments::_column_t>...> _columns;
+			std::tuple<typename Assignments::_value_t...> _values;
+			interpretable_list_t<Database> _dynamic_columns;
+			interpretable_list_t<Database> _dynamic_values;
+		};
+
+	template<typename Database, typename... Assignments>
+		struct insert_list_t
+		{
+			using _traits = make_traits<no_value_t, ::sqlpp::tag::insert_list>;
+			using _recursive_traits = make_recursive_traits<typename Assignments::_column_t..., typename Assignments::_value_t...>;
+
+			using _is_dynamic = is_database<Database>;
+
+			template<template<typename...> class Target>
+				using copy_assignments_t = Target<Assignments...>; // FIXME: Nice idea to copy variadic template arguments?
+			template<template<typename...> class Target, template<typename> class Wrap>
+				using copy_wrapped_assignments_t = Target<Wrap<Assignments>...>;
+
+			// Data
+			using _data_t = insert_list_data_t<Database, Assignments...>;
+
+			// Member implementation with data and methods
+			template <typename Policies>
+				struct _impl_t
+				{
+					template<typename Assignment>
+						void add_ntc(Assignment assignment)
+						{
+							add<Assignment, std::false_type>(assignment);
+						}
+
+					template<typename Assignment, typename TableCheckRequired = std::true_type>
+						void add(Assignment assignment)
+						{
+							static_assert(_is_dynamic::value, "add must not be called for static from()");
+							static_assert(is_assignment_t<Assignment>::value, "add() arguments require to be assigments");
+							using _assigned_columns = detail::make_type_set_t<typename Assignments::_column_t...>;
+							static_assert(not detail::is_element_of<typename Assignment::_column_t, _assigned_columns>::value, "Must not assign value to column twice");
+							static_assert(not must_not_insert_t<typename Assignment::_column_t>::value, "add() argument must not be used in insert");
+							static_assert(not TableCheckRequired::value or Policies::template _no_unknown_tables<Assignment>::value, "add() contains a column from a foreign table");
+
+							using ok = ::sqlpp::detail::all_t<
+								_is_dynamic::value, 
+								is_assignment_t<Assignment>::value>;
+
+							_add_impl(assignment, ok()); // dispatch to prevent compile messages after the static_assert
+						}
+
+				private:
+					template<typename Assignment>
+						void _add_impl(Assignment assignment, const std::true_type&)
+						{
+							_data._dynamic_columns.emplace_back(simple_column_t<typename Assignment::_column_t>{assignment._lhs});
+							_data._dynamic_values.emplace_back(assignment._rhs);
+						}
+
+					template<typename Assignment>
+						void _add_impl(Assignment assignment, const std::false_type&);
+				public:
+					_data_t _data;
+				};
+
+			// Member template for adding the named member to a statement
+			template<typename Policies>
+				struct _member_t
+				{
+					using _data_t = insert_list_data_t<Database, Assignments...>;
+
+					_impl_t<Policies> insert_list;
+					_impl_t<Policies>& operator()() { return insert_list; }
+					const _impl_t<Policies>& operator()() const { return insert_list; }
+
+					template<typename T>
+						static auto _get_member(T t) -> decltype(t.insert_list)
+						{
+							return t.insert_list;
+						}
+				};
+
+			// Additional methods for the statement
+			template<typename Policies>
+				struct _methods_t
+				{
+					static void _check_consistency() {}
+				};
+
+		};
+
+	template<typename... Columns>
+		struct column_list_data_t
+		{
+			column_list_data_t(Columns... columns):
+				_columns(simple_column_t<Columns>{columns}...)
+				{}
+
+			column_list_data_t(const column_list_data_t&) = default;
+			column_list_data_t(column_list_data_t&&) = default;
+			column_list_data_t& operator=(const column_list_data_t&) = default;
+			column_list_data_t& operator=(column_list_data_t&&) = default;
+			~column_list_data_t() = default;
+
+			using _value_tuple_t = std::tuple<insert_value_t<Columns>...>;
+			std::tuple<simple_column_t<Columns>...> _columns;
+			std::vector<_value_tuple_t> _insert_values;
+		};
+
+	template<typename... Columns>
+		struct column_list_t
+		{
+			using _traits = make_traits<no_value_t, ::sqlpp::tag::column_list>;
+			using _recursive_traits = make_recursive_traits<Columns...>;
+
+			static_assert(sizeof...(Columns), "at least one column required in columns()");
+
+			static_assert(not ::sqlpp::detail::has_duplicates<Columns...>::value, "at least one duplicate argument detected in columns()");
+
+			static_assert(::sqlpp::detail::all_t<is_column_t<Columns>::value...>::value, "at least one argument is not a column in columns()");
+
+			static_assert(::sqlpp::detail::none_t<must_not_insert_t<Columns>::value...>::value, "at least one column argument has a must_not_insert flag in its definition");
+
+			using _value_tuple_t = typename column_list_data_t<Columns...>::_value_tuple_t;
+
+			static_assert(required_tables_of<column_list_t>::size::value == 1, "columns from multiple tables in columns()");
+
+			// Data
+			using _data_t = column_list_data_t<Columns...>;
+
+			// Member implementation with data and methods
+			template <typename Policies>
+				struct _impl_t
+				{
+					template<typename... Assignments>
+						void add(Assignments... assignments)
+						{
+							static_assert(::sqlpp::detail::all_t<is_assignment_t<Assignments>::value...>::value, "add_values() arguments have to be assignments");
+							using _arg_value_tuple = std::tuple<insert_value_t<typename Assignments::_column_t>...>;
+							using _args_correct = std::is_same<_arg_value_tuple, _value_tuple_t>;
+							static_assert(_args_correct::value, "add_values() arguments do not match columns() arguments");
+
+							using ok = ::sqlpp::detail::all_t<
+								::sqlpp::detail::all_t<is_assignment_t<Assignments>::value...>::value, 
+								_args_correct::value>;
+
+							_add_impl(ok(), assignments...); // dispatch to prevent compile messages after the static_assert
+						}
+
+				private:
+					template<typename... Assignments>
+						void _add_impl(const std::true_type&, Assignments... assignments)
+						{
+							return _data._insert_values.emplace_back(insert_value_t<typename Assignments::_column_t>{assignments}...);
+						}
+
+					template<typename... Assignments>
+						void _add_impl(const std::false_type&, Assignments... assignments);
+				public:
+					_data_t _data;
+				};
+
+			// Member template for adding the named member to a statement
+			template<typename Policies>
+				struct _member_t
+				{
+					using _data_t = column_list_data_t<Columns...>;
+
+					_impl_t<Policies> values;
+					_impl_t<Policies>& operator()() { return values; }
+					const _impl_t<Policies>& operator()() const { return values; }
+
+					template<typename T>
+						static auto _get_member(T t) -> decltype(t.values)
+						{
+							return t.values;
+						}
+				};
+
+			// Additional methods for the statement
+			template<typename Policies>
+				struct _methods_t
+				{
+					static void _check_consistency() {}
+				};
+		};
+
+	// NO INSERT COLUMNS/VALUES YET
+	struct no_insert_value_list_t
+	{
+		using _traits = make_traits<no_value_t, ::sqlpp::tag::noop>;
+		using _recursive_traits = make_recursive_traits<>;
+
+		// Data
+		using _data_t = no_data_t;
+
+		// Member implementation with data and methods
+		template<typename Policies>
+			struct _impl_t
+			{
+				_data_t _data;
+			};
+
+		// Member template for adding the named member to a statement
+		template<typename Policies>
+			struct _member_t
+			{
+				using _data_t = no_data_t;
+
+				_impl_t<Policies> no_insert_values;
+				_impl_t<Policies>& operator()() { return no_insert_values; }
+				const _impl_t<Policies>& operator()() const { return no_insert_values; }
+
+				template<typename T>
+					static auto _get_member(T t) -> decltype(t.no_insert_values)
+					{
+						return t.no_insert_values;
+					}
+			};
+
+		template<typename Policies>
+			struct _methods_t
+			{
+				using _database_t = typename Policies::_database_t;
+				template<typename T>
+					using _new_statement_t = typename Policies::template _new_statement_t<no_insert_value_list_t, T>;
+
+				static void _check_consistency() {}
+
+				auto default_values()
+					-> _new_statement_t<insert_default_values_t>
+					{
+						return { *static_cast<typename Policies::_statement_t*>(this), insert_default_values_data_t{} };
+					}
+
+				template<typename... Args>
+					auto columns(Args... args)
+					-> _new_statement_t<column_list_t<Args...>>
+					{
+						return { *static_cast<typename Policies::_statement_t*>(this), column_list_data_t<Args...>{args...} };
+					}
+
+				template<typename... Assignments>
+					auto set(Assignments... assignments)
+					-> _new_statement_t<insert_list_t<void, Assignments...>>
+					{
+						static_assert(sizeof...(Assignments), "at least one assignment expression required in set()");
+						return _set_impl<void>(assignments...);
+					}
+
+				template<typename... Assignments>
+					auto dynamic_set(Assignments... assignments)
+					-> _new_statement_t<insert_list_t<_database_t, Assignments...>>
+					{
+						static_assert(not std::is_same<_database_t, void>::value, "dynamic_set must not be called in a static statement");
+						return _set_impl<_database_t>(assignments...);
+					}
+			private:
+				template<typename Database, typename... Assignments>
+					auto _set_impl(Assignments... assignments)
+					-> _new_statement_t<insert_list_t<Database, Assignments...>>
+					{
+						static_assert(not ::sqlpp::detail::has_duplicates<Assignments...>::value, "at least one duplicate argument detected in set()");
+						static_assert(sqlpp::detail::all_t<is_assignment_t<Assignments>::value...>::value, "at least one argument is not an assignment in set()");
+						static_assert(sqlpp::detail::none_t<must_not_insert_t<typename Assignments::_column_t>::value...>::value, "at least one assignment is prohibited by its column definition in set()");
+
+						using _column_required_tables = typename ::sqlpp::detail::make_joined_set<required_tables_of<typename Assignments::_column_t>...>::type;
+						static_assert(sizeof...(Assignments) ? (_column_required_tables::size::value == 1) : true, "set() contains assignments for columns from several tables");
+
+						return { *static_cast<typename Policies::_statement_t*>(this), insert_list_data_t<Database, Assignments...>{assignments...} };
+					}
+			};
+	};
+
+	// Interpreters
+	template<typename Context>
+		struct serializer_t<Context, insert_default_values_data_t>
+		{
+			using T = insert_default_values_data_t;
+
+			static Context& _(const T& t, Context& context)
+			{
+				context << " DEFAULT VALUES";
+				return context;
+			}
+		};
+
+	template<typename Context, typename... Columns>
+		struct serializer_t<Context, column_list_data_t<Columns...>>
+		{
+			using T = column_list_data_t<Columns...>;
+
+			static Context& _(const T& t, Context& context)
+			{
+				context << " (";
+				interpret_tuple(t._columns, ",", context);
+				context << ")";
+				context << " VALUES ";
+				bool first = true;
+				for (const auto& row : t._insert_values)
+				{
+					if (not first)
+						context << ',';
+					else
+						first = false;
+					context << '(';
+					interpret_tuple(row, ",", context);
+					context << ')';
+				}
+
+				return context;
+			}
+		};
+
+	template<typename Context, typename Database, typename... Assignments>
+		struct serializer_t<Context, insert_list_data_t<Database, Assignments...>>
+		{
+			using T = insert_list_data_t<Database, Assignments...>;
+
+			static Context& _(const T& t, Context& context)
+			{
+				if (sizeof...(Assignments) + t._dynamic_columns.size() == 0)
+				{
+					serialize(insert_default_values_data_t(), context);
+				}
+				else
+				{
+					context << " (";
+					interpret_tuple(t._columns, ",", context);
+					if (sizeof...(Assignments) and not t._dynamic_columns.empty())
+						context << ',';
+					interpret_list(t._dynamic_columns, ',', context);
+					context << ") VALUES(";
+					interpret_tuple(t._values, ",", context);
+					if (sizeof...(Assignments) and not t._dynamic_values.empty())
+						context << ',';
+					interpret_list(t._dynamic_values, ',', context);
+					context << ")";
+				}
+				return context;
+			}
+		};
+
+}
+
+#endif

include/sqlpp11/integral.h

@@ -32,7 +32,8 @@
 #include <sqlpp11/basic_expression_operators.h>
 #include <sqlpp11/type_traits.h>
 #include <sqlpp11/exception.h>
-#include <sqlpp11/vendor/value_type.h>
+#include <sqlpp11/value_type.h>
+#include <sqlpp11/assignment.h>
 
 namespace sqlpp
 {
@@ -42,15 +43,10 @@ namespace sqlpp
 		// integral value type
 		struct integral
 		{
-			using _value_type = integral;
-			using _base_value_type = integral;
-			using _is_numeric = std::true_type;
-			using _is_integral = std::true_type;
-			using _is_value = std::true_type;
-			using _is_expression = std::true_type;
+			using _traits = make_traits<integral, ::sqlpp::tag::expression>;
+			using _tag = ::sqlpp::tag::integral;
 			using _cpp_value_type = int64_t;
 
-			
 			struct _parameter_t
 			{
 				using _value_type = integral;
@@ -58,12 +54,12 @@ namespace sqlpp
 				_parameter_t():
 					_value(0),
 					_is_null(true)
-					{}
+				{}
 
 				explicit _parameter_t(const _cpp_value_type& value):
 					_value(value),
 					_is_null(false)
-					{}
+				{}
 
 				_parameter_t& operator=(const _cpp_value_type& value)
 				{
@@ -79,7 +75,7 @@ namespace sqlpp
 				}
 
 				bool is_null() const
-			 	{ 
+				{ 
 					return _is_null; 
 				}
 
@@ -102,145 +98,132 @@ namespace sqlpp
 			};
 
 			template<typename Db, bool NullIsTrivial = false>
-			struct _result_entry_t
-			{
-				using _value_type = integral;
+				struct _result_entry_t
+				{
+					using _value_type = integral;
 
-				_result_entry_t():
-					_is_valid(false),
-					_is_null(true),
-					_value(0)
+					_result_entry_t():
+						_is_valid(false),
+						_is_null(true),
+						_value(0)
 					{}
 
-				_result_entry_t(const char* data, size_t):
-					_is_valid(true),
-					_is_null(data == nullptr),
-					_value(_is_null ? 0 : std::strtoll(data, nullptr, 10))
-					{}
-
-				void assign(const char* data, size_t)
-				{
-					_is_valid = true;
-					_is_null = data == nullptr;
-					_value = _is_null ? 0 : std::strtoll(data, nullptr, 10);
-				}
-
-				void invalidate()
-				{
-					_is_valid = false;
-					_is_null = true;
-					_value = 0;
-				}
-
-				void validate()
-				{
-					_is_valid = true;
-				}
-
-				bool is_null() const
-			 	{ 
-					if (connector_assert_result_validity_t<Db>::value)
-						assert(_is_valid);
-					else if (not _is_valid)
-						throw exception("accessing is_null in non-existing row");
-					return _is_null; 
-				}
-
-				_cpp_value_type value() const
-				{
-					const bool null_value = _is_null and not NullIsTrivial and not connector_null_result_is_trivial_value_t<Db>::value;
-					if (connector_assert_result_validity_t<Db>::value)
+					void _invalidate()
 					{
-						assert(_is_valid);
-						assert(not null_value);
-					}
-					else
-					{
-						if (not _is_valid)
-							throw exception("accessing value in non-existing row");
-						if (null_value)
-							throw exception("accessing value of NULL field");
-					}
-					return _value;
-				}
-
-				operator _cpp_value_type() const { return value(); }
-
-				template<typename Target>
-					void _bind(Target& target, size_t i)
-					{
-						target._bind_integral_result(i, &_value, &_is_null);
+						_is_valid = false;
+						_is_null = true;
+						_value = 0;
 					}
 
-			private:
-				bool _is_valid;
-				bool _is_null;
-				_cpp_value_type _value;
-			};
+					void _validate()
+					{
+						_is_valid = true;
+					}
+
+					bool is_null() const
+					{ 
+						if (connector_assert_result_validity_t<Db>::value)
+							assert(_is_valid);
+						else if (not _is_valid)
+							throw exception("accessing is_null in non-existing row");
+						return _is_null; 
+					}
+
+					_cpp_value_type value() const
+					{
+						const bool null_value = _is_null and not NullIsTrivial and not connector_null_result_is_trivial_value_t<Db>::value;
+						if (connector_assert_result_validity_t<Db>::value)
+						{
+							assert(_is_valid);
+							assert(not null_value);
+						}
+						else
+						{
+							if (not _is_valid)
+								throw exception("accessing value in non-existing row");
+							if (null_value)
+								throw exception("accessing value of NULL field");
+						}
+						return _value;
+					}
+
+					operator _cpp_value_type() const { return value(); }
+
+					template<typename Target>
+						void _bind(Target& target, size_t i)
+						{
+							target._bind_integral_result(i, &_value, &_is_null);
+						}
+
+				private:
+					bool _is_valid;
+					bool _is_null;
+					_cpp_value_type _value;
+				};
 
 			template<typename T>
 				struct _is_valid_operand
-			{
-				static constexpr bool value = 
-					is_expression_t<T>::value // expressions are OK
-					and is_numeric_t<T>::value // the correct value type is required, of course
-					;
-			};
+				{
+					static constexpr bool value = 
+						is_expression_t<T>::value // expressions are OK
+						and is_numeric_t<T>::value // the correct value type is required, of course
+						;
+				};
 
 			template<typename Base>
 				struct expression_operators: public basic_expression_operators<Base, is_numeric_t>
 			{
 				template<typename T>
-					vendor::plus_t<Base, vendor::value_type_t<T>, vendor::wrap_operand_t<T>> operator +(T t) const
+					plus_t<Base, value_type_t<T>, wrap_operand_t<T>> operator +(T t) const
 					{
-						using rhs = vendor::wrap_operand_t<T>;
+						using rhs = wrap_operand_t<T>;
 						static_assert(_is_valid_operand<rhs>::value, "invalid rhs operand");
 
 						return { *static_cast<const Base*>(this), {t} };
 					}
 
 				template<typename T>
-					vendor::minus_t<Base, vendor::value_type_t<T>, vendor::wrap_operand_t<T>> operator -(T t) const
+					minus_t<Base, value_type_t<T>, wrap_operand_t<T>> operator -(T t) const
 					{
-						using rhs = vendor::wrap_operand_t<T>;
+						using rhs = wrap_operand_t<T>;
 						static_assert(_is_valid_operand<rhs>::value, "invalid rhs operand");
 
 						return { *static_cast<const Base*>(this), {t} };
 					}
 
 				template<typename T>
-					vendor::multiplies_t<Base, vendor::value_type_t<T>, vendor::wrap_operand_t<T>> operator *(T t) const
+					multiplies_t<Base, value_type_t<T>, wrap_operand_t<T>> operator *(T t) const
 					{
-						using rhs = vendor::wrap_operand_t<T>;
+						using rhs = wrap_operand_t<T>;
 						static_assert(_is_valid_operand<rhs>::value, "invalid rhs operand");
 
 						return { *static_cast<const Base*>(this), {t} };
 					}
 
 				template<typename T>
-					vendor::divides_t<Base, vendor::wrap_operand_t<T>> operator /(T t) const
+					divides_t<Base, wrap_operand_t<T>> operator /(T t) const
 					{
-						using rhs = vendor::wrap_operand_t<T>;
+						using rhs = wrap_operand_t<T>;
 						static_assert(_is_valid_operand<rhs>::value, "invalid rhs operand");
 
 						return { *static_cast<const Base*>(this), {t} };
 					}
 
 				template<typename T>
-					vendor::modulus_t<Base, vendor::wrap_operand_t<T>> operator %(T t) const
+					modulus_t<Base, wrap_operand_t<T>> operator %(T t) const
 					{
-						using rhs = vendor::wrap_operand_t<T>;
+						using rhs = wrap_operand_t<T>;
 						static_assert(_is_valid_operand<rhs>::value, "invalid rhs operand");
 
 						return { *static_cast<const Base*>(this), {t} };
 					}
 
-				vendor::unary_plus_t<integral, Base> operator +() const
+				unary_plus_t<integral, Base> operator +() const
 				{
 					return { *static_cast<const Base*>(this) };
 				}
 
-				vendor::unary_minus_t<integral, Base> operator -() const
+				unary_minus_t<integral, Base> operator -() const
 				{
 					return { *static_cast<const Base*>(this) };
 				}
@@ -248,50 +231,50 @@ namespace sqlpp
 
 			template<typename Base>
 				struct column_operators
-			{
-				template<typename T>
-					auto operator +=(T t) const -> vendor::assignment_t<Base, vendor::plus_t<Base, vendor::value_type_t<T>, vendor::wrap_operand_t<T>>>
-					{
-						using rhs = vendor::wrap_operand_t<T>;
-						static_assert(_is_valid_operand<rhs>::value, "invalid rhs assignment operand");
+				{
+					template<typename T>
+						auto operator +=(T t) const -> assignment_t<Base, plus_t<Base, value_type_t<T>, wrap_operand_t<T>>>
+						{
+							using rhs = wrap_operand_t<T>;
+							static_assert(_is_valid_operand<rhs>::value, "invalid rhs assignment operand");
 
-						return { *static_cast<const Base*>(this), { *static_cast<const Base*>(this), rhs{t} } };
-					}
+							return { *static_cast<const Base*>(this), { *static_cast<const Base*>(this), rhs{t} } };
+						}
 
-				template<typename T>
-					auto operator -=(T t) const -> vendor::assignment_t<Base, vendor::minus_t<Base, vendor::value_type_t<T>, vendor::wrap_operand_t<T>>>
-					{
-						using rhs = vendor::wrap_operand_t<T>;
-						static_assert(_is_valid_operand<rhs>::value, "invalid rhs assignment operand");
+					template<typename T>
+						auto operator -=(T t) const -> assignment_t<Base, minus_t<Base, value_type_t<T>, wrap_operand_t<T>>>
+						{
+							using rhs = wrap_operand_t<T>;
+							static_assert(_is_valid_operand<rhs>::value, "invalid rhs assignment operand");
 
-						return { *static_cast<const Base*>(this), { *static_cast<const Base*>(this), rhs{t} } };
-					}
+							return { *static_cast<const Base*>(this), { *static_cast<const Base*>(this), rhs{t} } };
+						}
 
-				template<typename T>
-					auto operator /=(T t) const -> vendor::assignment_t<Base, vendor::divides_t<Base, vendor::wrap_operand_t<T>>>
-					{
-						using rhs = vendor::wrap_operand_t<T>;
-						static_assert(_is_valid_operand<rhs>::value, "invalid rhs assignment operand");
+					template<typename T>
+						auto operator /=(T t) const -> assignment_t<Base, divides_t<Base, wrap_operand_t<T>>>
+						{
+							using rhs = wrap_operand_t<T>;
+							static_assert(_is_valid_operand<rhs>::value, "invalid rhs assignment operand");
 
-						return { *static_cast<const Base*>(this), { *static_cast<const Base*>(this), rhs{t} } };
-					}
+							return { *static_cast<const Base*>(this), { *static_cast<const Base*>(this), rhs{t} } };
+						}
 
-				template<typename T>
-					auto operator *=(T t) const -> vendor::assignment_t<Base, vendor::multiplies_t<Base, vendor::value_type_t<T>, vendor::wrap_operand_t<T>>>
-					{
-						using rhs = vendor::wrap_operand_t<T>;
-						static_assert(_is_valid_operand<rhs>::value, "invalid rhs assignment operand");
+					template<typename T>
+						auto operator *=(T t) const -> assignment_t<Base, multiplies_t<Base, value_type_t<T>, wrap_operand_t<T>>>
+						{
+							using rhs = wrap_operand_t<T>;
+							static_assert(_is_valid_operand<rhs>::value, "invalid rhs assignment operand");
 
-						return { *static_cast<const Base*>(this), { *static_cast<const Base*>(this), rhs{t} } };
-					}
-			};
+							return { *static_cast<const Base*>(this), { *static_cast<const Base*>(this), rhs{t} } };
+						}
+				};
 		};
 
 		template<typename Db, bool NullIsTrivial>
-		inline std::ostream& operator<<(std::ostream& os, const integral::_result_entry_t<Db, NullIsTrivial>& e)
-		{
-			return os << e.value();
-		}
+			inline std::ostream& operator<<(std::ostream& os, const integral::_result_entry_t<Db, NullIsTrivial>& e)
+			{
+				return os << e.value();
+			}
 	}
 
 	using tinyint = detail::integral;

include/sqlpp11/interpret.h

@@ -27,15 +27,15 @@
 #ifndef SQLPP_INTERPRET_H
 #define SQLPP_INTERPRET_H
 
-#include <sqlpp11/vendor/interpreter.h>
+#include <sqlpp11/interpreter.h>
 
 namespace sqlpp
 {
 	template<typename T, typename Context>
 		auto interpret(const T& t, Context& context)
-		-> decltype(vendor::interpreter_t<Context, T>::_(t, context))
+		-> decltype(interpreter_t<Context, T>::_(t, context))
 		{
-			return vendor::interpreter_t<Context, T>::_(t, context);
+			return interpreter_t<Context, T>::_(t, context);
 		}
 
 }

include/sqlpp11/interpret_tuple.h

@@ -50,7 +50,7 @@ namespace sqlpp
 		auto interpret_tuple_impl(const Tuple& t, const Separator& separator, Context& context, const ::sqlpp::detail::index_sequence<Is...>&)
 		-> Context&
 		{
-      // Note: A braced-init-list does guarantee the order of evaluation according to 12.6.1 [class.explicit.init] paragraph 2 and 8.5.4 [dcl.init.list] paragraph 4.
+			// Note: A braced-init-list does guarantee the order of evaluation according to 12.6.1 [class.explicit.init] paragraph 2 and 8.5.4 [dcl.init.list] paragraph 4.
 			// See for example: "http://en.cppreference.com/w/cpp/utility/integer_sequence"
 			// See also: "http://stackoverflow.com/questions/6245735/pretty-print-stdtuple/6245777#6245777"
 			// Beware of gcc-bug: "http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51253", otherwise an empty swallow struct could be used

include/sqlpp11/interpretable.h

@@ -0,0 +1,128 @@
+/*
+ * Copyright (c) 2013-2014, Roland Bock
+ * All rights reserved.
+ * 
+ * Redistribution and use in source and binary forms, with or without modification,
+ * are permitted provided that the following conditions are met:
+ * 
+ *   Redistributions of source code must retain the above copyright notice, this
+ *   list of conditions and the following disclaimer.
+ * 
+ *   Redistributions in binary form must reproduce the above copyright notice, this
+ *   list of conditions and the following disclaimer in the documentation and/or
+ *   other materials provided with the distribution.
+ * 
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR
+ * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+ * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef SQLPP_INTERPRETABLE_H
+#define SQLPP_INTERPRETABLE_H
+
+#include <memory>
+#include <sqlpp11/serializer_context.h>
+#include <sqlpp11/parameter_list.h>
+#include <sqlpp11/serialize.h>
+#include <sqlpp11/interpret.h>
+
+namespace sqlpp
+{
+	template<typename Db>
+		struct interpretable_t
+		{
+			using _serializer_context_t = typename Db::_serializer_context_t;
+			using _interpreter_context_t = typename Db::_interpreter_context_t;
+
+			template<typename T>
+				interpretable_t(T t):
+					_impl(std::make_shared<_impl_t<T>>(t))
+			{}
+
+			interpretable_t(const interpretable_t&) = default;
+			interpretable_t(interpretable_t&&) = default;
+			interpretable_t& operator=(const interpretable_t&) = default;
+			interpretable_t& operator=(interpretable_t&&) = default;
+			~interpretable_t() = default;
+
+			sqlpp::serializer_context_t& serialize(sqlpp::serializer_context_t& context) const
+			{
+				return _impl->serialize(context);
+			}
+
+			// This method only exists if Db::_serializer_context_t and sqlpp::serializer_context_t are not the same
+			template<typename Context>
+				auto serialize(Context& context) const
+				-> typename std::enable_if<std::is_same<Context, _serializer_context_t>::value 
+				and not std::is_same<Context, sqlpp::serializer_context_t>::value, Context&>::type
+				{
+					return _impl->db_serialize(context);
+				}
+
+			_interpreter_context_t& interpret(_interpreter_context_t& context) const
+			{
+				return _impl->interpret(context);
+			}
+
+		private:
+			struct _impl_base
+			{
+				virtual sqlpp::serializer_context_t& serialize(sqlpp::serializer_context_t& context) const = 0;
+				virtual _serializer_context_t& db_serialize(_serializer_context_t& context) const = 0;
+				virtual _interpreter_context_t& interpret(_interpreter_context_t& context) const = 0;
+			};
+
+			template<typename T>
+				struct _impl_t: public _impl_base
+			{
+				static_assert(not make_parameter_list_t<T>::size::value, "parameters not supported in dynamic statement parts");
+				_impl_t(T t):
+					_t(t)
+				{}
+
+				sqlpp::serializer_context_t& serialize(sqlpp::serializer_context_t& context) const
+				{
+					sqlpp::serialize(_t, context);
+					return context;
+				}
+
+				_serializer_context_t& db_serialize(_serializer_context_t& context) const
+				{
+					Db::_serialize_interpretable(_t, context);
+					return context;
+				}
+
+				_interpreter_context_t& interpret(_interpreter_context_t& context) const
+				{
+					Db::_interpret_interpretable(_t, context);
+					return context;
+				}
+
+				T _t;
+			};
+
+			std::shared_ptr<const _impl_base> _impl;
+		};
+
+	template<typename Context, typename Database>
+		struct serializer_t<Context, interpretable_t<Database>>
+		{
+			using T = interpretable_t<Database>;
+
+			static Context& _(const T& t, Context& context)
+			{
+				t.serialize(context);
+				return context;
+			}
+		};
+
+}
+
+#endif

include/sqlpp11/interpretable_list.h

@@ -28,92 +28,89 @@
 #define SQLPP_INTERPRETABLE_LIST_H
 
 #include <vector>
-#include <sqlpp11/vendor/interpretable.h>
+#include <sqlpp11/interpretable.h>
 
 namespace sqlpp
 {
-	namespace vendor
-	{
-		template<typename Db>
-			struct interpretable_list_t
+	template<typename Db>
+		struct interpretable_list_t
+		{
+			std::vector<interpretable_t<Db>> _serializables;
+
+			std::size_t size() const
 			{
-				std::vector<interpretable_t<Db>> _serializables;
+				return _serializables.size();
+			}
 
-				std::size_t size() const
-				{
-					return _serializables.size();
-				}
+			bool empty() const
+			{
+				return _serializables.empty();
+			}
 
-				bool empty() const
-				{
-					return _serializables.empty();
-				}
-
-				template<typename Expr>
+			template<typename Expr>
 				void emplace_back(Expr expr)
 				{
 					_serializables.emplace_back(expr);
 				}
 
-			};
+		};
 
-		template<>
-			struct interpretable_list_t<void>
+	template<>
+		struct interpretable_list_t<void>
+		{
+			static constexpr std::size_t size()
 			{
-				static constexpr std::size_t size()
-				{
-					return 0;
-				}
-
-				static constexpr bool empty()
-				{
-					return true;
-				}
-
-			};
-
-		template<typename Context, typename List>
-			struct serializable_list_interpreter_t
-			{
-				using T = List;
-
-				template<typename Separator>
-					static Context& _(const T& t, const Separator& separator, Context& context)
-					{
-						bool first = true;
-						for (const auto entry : t._serializables)
-						{
-							if (not first)
-							{
-								context << separator;
-								first = false;
-							}
-							serialize(entry, context);
-						}
-						return context;
-					}
-			};
-
-		template<typename Context>
-			struct serializable_list_interpreter_t<Context, interpretable_list_t<void>>
-			{
-				using T = interpretable_list_t<void>;
-
-				template<typename Separator>
-					static Context& _(const T& t, const Separator& separator, Context& context)
-					{
-						return context;
-					}
-			};
-
-		template<typename T, typename Separator, typename Context>
-			auto interpret_list(const T& t, const Separator& separator, Context& context)
-			-> decltype(serializable_list_interpreter_t<Context, T>::_(t, separator, context))
-			{
-				return serializable_list_interpreter_t<Context, T>::_(t, separator, context);
+				return 0;
 			}
 
-	}
+			static constexpr bool empty()
+			{
+				return true;
+			}
+
+		};
+
+	template<typename Context, typename List>
+		struct serializable_list_interpreter_t
+		{
+			using T = List;
+
+			template<typename Separator>
+				static Context& _(const T& t, const Separator& separator, Context& context)
+				{
+					bool first = true;
+					for (const auto entry : t._serializables)
+					{
+						if (not first)
+						{
+							context << separator;
+							first = false;
+						}
+						serialize(entry, context);
+					}
+					return context;
+				}
+		};
+
+	template<typename Context>
+		struct serializable_list_interpreter_t<Context, interpretable_list_t<void>>
+		{
+			using T = interpretable_list_t<void>;
+
+			template<typename Separator>
+				static Context& _(const T& t, const Separator& separator, Context& context)
+				{
+					return context;
+				}
+		};
+
+	template<typename T, typename Separator, typename Context>
+		auto interpret_list(const T& t, const Separator& separator, Context& context)
+		-> decltype(serializable_list_interpreter_t<Context, T>::_(t, separator, context))
+		{
+			return serializable_list_interpreter_t<Context, T>::_(t, separator, context);
+		}
+
 }
 
 #endif

include/sqlpp11/interpreter.h

@@ -24,24 +24,21 @@
  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
-#ifndef SQLPP_VENDOR_INTERPRETER_H
-#define SQLPP_VENDOR_INTERPRETER_H
+#ifndef SQLPP_INTERPRETER_H
+#define SQLPP_INTERPRETER_H
 
-#include <sqlpp11/vendor/wrong.h>
+#include <sqlpp11/wrong.h>
 
 namespace sqlpp
 {
-	namespace vendor
-	{
-		template<typename Context, typename T, typename Enable = void>
-			struct interpreter_t
+	template<typename Context, typename T, typename Enable = void>
+		struct interpreter_t
+		{
+			static void _(const T& t, Context& context)
 			{
-				static void _(const T& t, Context& context)
-				{
-					static_assert(wrong_t<Context, T>::value, "missing interpreter specialization");
-				}
-			};
-	}
+				static_assert(wrong_t<Context, T>::value, "missing interpreter specialization");
+			}
+		};
 
 }
 

include/sqlpp11/into.h

@@ -0,0 +1,173 @@
+/*
+ * Copyright (c) 2013-2014, Roland Bock
+ * All rights reserved.
+ * 
+ * Redistribution and use in source and binary forms, with or without modification,
+ * are permitted provided that the following conditions are met:
+ * 
+ *   Redistributions of source code must retain the above copyright notice, this
+ *   list of conditions and the following disclaimer.
+ * 
+ *   Redistributions in binary form must reproduce the above copyright notice, this
+ *   list of conditions and the following disclaimer in the documentation and/or
+ *   other materials provided with the distribution.
+ * 
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR
+ * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+ * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef SQLPP_INTO_H
+#define SQLPP_INTO_H
+
+#include <sqlpp11/type_traits.h>
+#include <sqlpp11/no_value.h>
+#include <sqlpp11/no_data.h>
+#include <sqlpp11/prepared_insert.h>
+#include <sqlpp11/serializer.h>
+#include <sqlpp11/detail/type_set.h>
+
+namespace sqlpp
+{
+	// A SINGLE TABLE DATA
+	template<typename Database, typename Table>
+		struct into_data_t
+		{
+			into_data_t(Table table):
+				_table(table)
+			{}
+
+			into_data_t(const into_data_t&) = default;
+			into_data_t(into_data_t&&) = default;
+			into_data_t& operator=(const into_data_t&) = default;
+			into_data_t& operator=(into_data_t&&) = default;
+			~into_data_t() = default;
+
+			Table _table;
+		};
+
+	// A SINGLE TABLE
+	template<typename Database, typename Table>
+		struct into_t
+		{
+			using _traits = make_traits<no_value_t, ::sqlpp::tag::into>;
+			using _recursive_traits = make_recursive_traits<Table>;
+
+			static_assert(is_table_t<Table>::value, "argument has to be a table");
+			static_assert(required_tables_of<Table>::size::value == 0, "table depends on another table");
+
+			using _data_t = into_data_t<Database, Table>;
+
+			struct _name_t {};
+
+			// Member implementation with data and methods
+			template <typename Policies>
+				struct _impl_t
+				{
+					_data_t _data;
+				};
+
+			// Member template for adding the named member to a statement
+			template<typename Policies>
+				struct _member_t
+				{
+					using _data_t = into_data_t<Database, Table>;
+
+					_impl_t<Policies> into;
+					_impl_t<Policies>& operator()() { return into; }
+					const _impl_t<Policies>& operator()() const { return into; }
+
+					template<typename T>
+						static auto _get_member(T t) -> decltype(t.into)
+						{
+							return t.into;
+						}
+				};
+
+			// Additional methods for the statement
+			template<typename Policies>
+				struct _methods_t
+				{
+					static void _check_consistency() {}
+				};
+
+		};
+
+	// NO INTO YET
+	struct no_into_t
+	{
+		using _traits = make_traits<no_value_t, ::sqlpp::tag::noop>;
+		using _recursive_traits = make_recursive_traits<>;
+
+		// Data
+		using _data_t = no_data_t;
+
+		// Member implementation with data and methods
+		template<typename Policies>
+			struct _impl_t
+			{
+				_data_t _data;
+			};
+
+		// Member template for adding the named member to a statement
+		template<typename Policies>
+			struct _member_t
+			{
+				using _data_t = no_data_t;
+
+				_impl_t<Policies> no_into;
+				_impl_t<Policies>& operator()() { return no_into; }
+				const _impl_t<Policies>& operator()() const { return no_into; }
+
+				template<typename T>
+					static auto _get_member(T t) -> decltype(t.no_into)
+					{
+						return t.no_into;
+					}
+			};
+
+		template<typename Policies>
+			struct _methods_t
+			{
+				using _database_t = typename Policies::_database_t;
+				template<typename T>
+					using _new_statement_t = typename Policies::template _new_statement_t<no_into_t, T>;
+
+					static void _check_consistency()
+					{
+						static_assert(wrong_t<Policies>::value, "into() required");
+					}
+
+				template<typename... Args>
+					auto into(Args... args)
+					-> _new_statement_t<into_t<void, Args...>>
+					{
+						return { *static_cast<typename Policies::_statement_t*>(this), into_data_t<void, Args...>{args...} };
+					}
+			};
+	};
+
+	// Interpreters
+	template<typename Context, typename Database, typename Table>
+		struct serializer_t<Context, into_data_t<Database, Table>>
+		{
+			using T = into_data_t<Database, Table>;
+
+			static Context& _(const T& t, Context& context)
+			{
+				context << " INTO ";
+				serialize(t._table, context);
+				return context;
+			}
+		};
+
+}
+
+#endif

include/sqlpp11/is_null.h

@@ -33,55 +33,55 @@
 
 namespace sqlpp
 {
-	namespace vendor
+	template<bool NotInverted, typename Operand>
+		struct is_null_t: public boolean::template expression_operators<is_null_t<NotInverted, Operand>>,
+		public alias_operators<is_null_t<NotInverted, Operand>>
 	{
-		template<bool NotInverted, typename Operand>
-		struct is_null_t: public boolean::template expression_operators<is_null_t<NotInverted, Operand>>
+		using _traits = make_traits<boolean, ::sqlpp::tag::expression, ::sqlpp::tag::named_expression>;
+		using _recursive_traits = make_recursive_traits<Operand>;
+
+		static constexpr bool _inverted = not NotInverted;
+
+		struct _value_type: public boolean
 		{
-			static constexpr bool _inverted = not NotInverted;
-			using _table_set = typename Operand::_table_set;
-
-			struct _value_type: public boolean
-			{
-				using _is_named_expression = std::true_type;
-			};
-
-			struct _name_t
-			{
-				static constexpr const char* _get_name() { return _inverted ? "IS NOT NULL" : "IS NULL"; }
-				template<typename T>
-					struct _member_t
-					{
-						T in;
-					};
-			};
-
-			is_null_t(Operand operand):
-				_operand(operand)
-			{}
-
-			is_null_t(const is_null_t&) = default;
-			is_null_t(is_null_t&&) = default;
-			is_null_t& operator=(const is_null_t&) = default;
-			is_null_t& operator=(is_null_t&&) = default;
-			~is_null_t() = default;
-
-			Operand _operand;
+			using _is_named_expression = std::true_type;
 		};
 
-		template<typename Context, bool NotInverted, typename Operand>
-			struct serializer_t<Context, ::sqlpp::vendor::is_null_t<NotInverted, Operand>>
-			{
-				using T = ::sqlpp::vendor::is_null_t<NotInverted, Operand>;
-
-				static Context& _(const T& t, Context& context)
+		struct _name_t
+		{
+			static constexpr const char* _get_name() { return _inverted ? "IS NOT NULL" : "IS NULL"; }
+			template<typename T>
+				struct _member_t
 				{
-					serialize(t._operand, context);
-					context << (t._inverted ? " IS NOT NULL" : " IS NULL");
-					return context;
-				}
-			};
-	}
+					T in;
+				};
+		};
+
+		is_null_t(Operand operand):
+			_operand(operand)
+		{}
+
+		is_null_t(const is_null_t&) = default;
+		is_null_t(is_null_t&&) = default;
+		is_null_t& operator=(const is_null_t&) = default;
+		is_null_t& operator=(is_null_t&&) = default;
+		~is_null_t() = default;
+
+		Operand _operand;
+	};
+
+	template<typename Context, bool NotInverted, typename Operand>
+		struct serializer_t<Context, ::sqlpp::is_null_t<NotInverted, Operand>>
+		{
+			using T = ::sqlpp::is_null_t<NotInverted, Operand>;
+
+			static Context& _(const T& t, Context& context)
+			{
+				serialize(t._operand, context);
+				context << (t._inverted ? " IS NOT NULL" : " IS NULL");
+				return context;
+			}
+		};
 
 }
 

include/sqlpp11/is_null_fwd.h

@@ -29,11 +29,8 @@
 
 namespace sqlpp
 {
-	namespace vendor
-	{
-		template<bool NotInverted, typename Operand>
+	template<bool NotInverted, typename Operand>
 		struct is_null_t;
-	}
 }
 
 #endif

include/sqlpp11/join.h

@@ -29,7 +29,7 @@
 
 #include <sqlpp11/type_traits.h>
 #include <sqlpp11/on.h>
-#include <sqlpp11/vendor/noop.h>
+#include <sqlpp11/noop.h>
 
 namespace sqlpp
 {
@@ -74,19 +74,20 @@ namespace sqlpp
 		static constexpr const char* _name = " RIGHT OUTER ";
 	};
 
-	template<typename JoinType, typename Lhs, typename Rhs, typename On = vendor::noop>
+	template<typename JoinType, typename Lhs, typename Rhs, typename On = noop>
 		struct join_t
 		{
+			using _traits = make_traits<no_value_t, tag::table, tag::join>;
+			using _recursive_traits = make_recursive_traits<Lhs, Rhs>;
+
 			static_assert(is_table_t<Lhs>::value, "lhs argument for join() has to be a table or join");
 			static_assert(is_table_t<Rhs>::value, "rhs argument for join() has to be a table");
 			static_assert(not is_join_t<Rhs>::value, "rhs argument for join must not be a join");
-			static_assert(vendor::is_noop<On>::value or is_on_t<On>::value, "invalid on expression in join().on()");
+			static_assert(is_noop<On>::value or is_on_t<On>::value, "invalid on expression in join().on()");
 
-			static_assert(::sqlpp::detail::is_disjunct_from<typename Lhs::_table_set, typename Rhs::_table_set>::value, "joined tables must not be identical");
+			static_assert(::sqlpp::detail::is_disjunct_from<provided_tables_of<Lhs>, provided_tables_of<Rhs>>::value, "joined tables must not be identical");
 
-			using _is_table = std::true_type;
-			using _is_join = std::true_type;
-			using _table_set = typename ::sqlpp::detail::make_joined_set<typename Lhs::_table_set, typename Rhs::_table_set>::type;
+			static_assert(_recursive_traits::_required_tables::size::value == 0, "joined tables must not depend on other tables");
 
 			template<typename OnT> 
 				using set_on_t = join_t<JoinType, Lhs, Rhs, OnT>;
@@ -95,7 +96,7 @@ namespace sqlpp
 				auto on(Expr... expr)
 				-> set_on_t<on_t<void, Expr...>>
 				{
-					static_assert(vendor::is_noop<On>::value, "cannot call on() twice for a single join()");
+					static_assert(is_noop<On>::value, "cannot call on() twice for a single join()");
 					return { _lhs, 
 						_rhs, 
 						{std::tuple<Expr...>{expr...}}
@@ -105,35 +106,35 @@ namespace sqlpp
 			template<typename T>
 				join_t<inner_join_t, join_t, T> join(T t)
 				{
-					static_assert(not vendor::is_noop<On>::value, "join type requires on()");
+					static_assert(not is_noop<On>::value, "join type requires on()");
 					return { *this, t };
 				}
 
 			template<typename T>
 				join_t<inner_join_t, join_t, T> inner_join(T t)
 				{
-					static_assert(not vendor::is_noop<On>::value, "join type requires on()");
+					static_assert(not is_noop<On>::value, "join type requires on()");
 					return { *this, t };
 				}
 
 			template<typename T>
 				join_t<outer_join_t, join_t, T> outer_join(T t)
 				{
-					static_assert(not vendor::is_noop<On>::value, "join type requires on()");
+					static_assert(not is_noop<On>::value, "join type requires on()");
 					return { *this, t };
 				}
 
 			template<typename T>
 				join_t<left_outer_join_t, join_t, T> left_outer_join(T t)
 				{
-					static_assert(not vendor::is_noop<On>::value, "join type requires on()");
+					static_assert(not is_noop<On>::value, "join type requires on()");
 					return { *this, t };
 				}
 
 			template<typename T>
 				join_t<right_outer_join_t, join_t, T> right_outer_join(T t)
 				{
-					static_assert(not vendor::is_noop<On>::value, "join type requires on()");
+					static_assert(not is_noop<On>::value, "join type requires on()");
 					return { *this, t };
 				}
 
@@ -142,26 +143,23 @@ namespace sqlpp
 			On _on;
 		};
 
-	namespace vendor
-	{
-		template<typename Context, typename JoinType, typename Lhs, typename Rhs, typename On>
-			struct serializer_t<Context, join_t<JoinType, Lhs, Rhs, On>>
+	template<typename Context, typename JoinType, typename Lhs, typename Rhs, typename On>
+		struct serializer_t<Context, join_t<JoinType, Lhs, Rhs, On>>
+		{
+			using T = join_t<JoinType, Lhs, Rhs, On>;
+
+			static Context& _(const T& t, Context& context)
 			{
-				using T = join_t<JoinType, Lhs, Rhs, On>;
+				static_assert(not is_noop<On>::value, "joined tables require on()");
+				serialize(t._lhs, context);
+				context << JoinType::_name;
+				context << " JOIN ";
+				serialize(t._rhs, context);
+				serialize(t._on, context);
+				return context;
+			}
+		};
 
-				static Context& _(const T& t, Context& context)
-				{
-					static_assert(not vendor::is_noop<On>::value, "joined tables require on()");
-					serialize(t._lhs, context);
-					context << JoinType::_name;
-					context << " JOIN ";
-					serialize(t._rhs, context);
-					serialize(t._on, context);
-					return context;
-				}
-			};
-
-	}
 }
 
 #endif

include/sqlpp11/like.h

@@ -33,61 +33,55 @@
 
 namespace sqlpp
 {
-	namespace vendor
+	template<typename Operand, typename Pattern>
+		struct like_t: public boolean::template expression_operators<like_t<Operand, Pattern>>,
+		public alias_operators<like_t<Operand, Pattern>>
 	{
-		template<typename Operand, typename Pattern>
-			struct like_t: public boolean::template expression_operators<like_t<Operand, Pattern>>
+		using _traits = make_traits<boolean, ::sqlpp::tag::expression, ::sqlpp::tag::named_expression>;
+		using _recursive_traits = make_recursive_traits<Operand, Pattern>;
+
+		static_assert(is_text_t<Operand>::value, "Operand for like() has to be a text");
+		static_assert(is_text_t<Pattern>::value, "Pattern for like() has to be a text");
+
+		struct _name_t
 		{
-			static_assert(is_text_t<Operand>::value, "Operand for like() has to be a text");
-			static_assert(is_text_t<Pattern>::value, "Pattern for like() has to be a text");
-			using _parameter_tuple_t = std::tuple<Operand, Pattern>;
-			using _table_set = typename ::sqlpp::detail::make_joined_set<typename Operand::_table_set, typename Pattern::_table_set>::type;
-
-			struct _value_type: public boolean
-			{
-				using _is_named_expression = std::true_type;
-			};
-
-			struct _name_t
-			{
-				static constexpr const char* _get_name() { return "LIKE"; }
-				template<typename T>
-					struct _member_t
-					{
-						T like;
-					};
-			};
-
-			like_t(Operand operand, Pattern pattern):
-				_operand(operand),
-				_pattern(pattern)
-			{}
-
-			like_t(const like_t&) = default;
-			like_t(like_t&&) = default;
-			like_t& operator=(const like_t&) = default;
-			like_t& operator=(like_t&&) = default;
-			~like_t() = default;
-
-			Operand _operand;
-			Pattern _pattern;
+			static constexpr const char* _get_name() { return "LIKE"; }
+			template<typename T>
+				struct _member_t
+				{
+					T like;
+				};
 		};
 
-		template<typename Context, typename Operand, typename Pattern>
-			struct serializer_t<Context, like_t<Operand, Pattern>>
-			{
-				using T = like_t<Operand, Pattern>;
+		like_t(Operand operand, Pattern pattern):
+			_operand(operand),
+			_pattern(pattern)
+		{}
 
-				static Context& _(const T& t, Context& context)
-				{
-					serialize(t._operand, context);
-					context << " LIKE(";
-					serialize(t._pattern, context);
-					context << ")";
-					return context;
-				}
-			};
-	}
+		like_t(const like_t&) = default;
+		like_t(like_t&&) = default;
+		like_t& operator=(const like_t&) = default;
+		like_t& operator=(like_t&&) = default;
+		~like_t() = default;
+
+		Operand _operand;
+		Pattern _pattern;
+	};
+
+	template<typename Context, typename Operand, typename Pattern>
+		struct serializer_t<Context, like_t<Operand, Pattern>>
+		{
+			using T = like_t<Operand, Pattern>;
+
+			static Context& _(const T& t, Context& context)
+			{
+				serialize(t._operand, context);
+				context << " LIKE(";
+				serialize(t._pattern, context);
+				context << ")";
+				return context;
+			}
+		};
 }
 
 #endif

include/sqlpp11/limit.h

@@ -0,0 +1,261 @@
+/*
+ * Copyright (c) 2013-2014, Roland Bock
+ * All rights reserved.
+ * 
+ * Redistribution and use in source and binary forms, with or without modification,
+ * are permitted provided that the following conditions are met:
+ * 
+ *   Redistributions of source code must retain the above copyright notice, this
+ *   list of conditions and the following disclaimer.
+ * 
+ *   Redistributions in binary form must reproduce the above copyright notice, this
+ *   list of conditions and the following disclaimer in the documentation and/or
+ *   other materials provided with the distribution.
+ * 
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR
+ * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+ * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef SQLPP_LIMIT_H
+#define SQLPP_LIMIT_H
+
+#include <sqlpp11/type_traits.h>
+#include <sqlpp11/policy_update.h>
+#include <sqlpp11/detail/type_set.h>
+
+namespace sqlpp
+{
+	// LIMIT DATA
+	template<typename Limit>
+		struct limit_data_t
+		{
+			limit_data_t(Limit value):
+				_value(value)
+			{}
+
+			limit_data_t(const limit_data_t&) = default;
+			limit_data_t(limit_data_t&&) = default;
+			limit_data_t& operator=(const limit_data_t&) = default;
+			limit_data_t& operator=(limit_data_t&&) = default;
+			~limit_data_t() = default;
+
+			Limit _value;
+		};
+
+	// LIMIT
+	template<typename Limit>
+		struct limit_t
+		{
+			using _traits = make_traits<no_value_t, ::sqlpp::tag::limit>;
+			using _recursive_traits = make_recursive_traits<Limit>;
+
+			static_assert(is_integral_t<Limit>::value, "limit requires an integral value or integral parameter");
+
+			// Data
+			using _data_t = limit_data_t<Limit>;
+
+			// Member implementation with data and methods
+			template <typename Policies>
+				struct _impl_t
+				{
+					_data_t _data;
+				};
+
+			// Member template for adding the named member to a statement
+			template<typename Policies>
+				struct _member_t
+				{
+					using _data_t = limit_data_t<Limit>;
+
+					_impl_t<Policies> limit;
+					_impl_t<Policies>& operator()() { return limit; }
+					const _impl_t<Policies>& operator()() const { return limit; }
+
+					template<typename T>
+						static auto _get_member(T t) -> decltype(t.limit)
+						{
+							return t.limit;
+						}
+				};
+
+			template<typename Policies>
+				struct _methods_t
+				{
+					static void _check_consistency() {}
+				};
+		};
+
+	// DYNAMIC LIMIT DATA
+	template<typename Database>
+		struct dynamic_limit_data_t
+		{
+			dynamic_limit_data_t():
+				_value(noop())
+			{
+			}
+
+			template<typename Limit>
+				dynamic_limit_data_t(Limit value):
+					_initialized(true),
+					_value(typename wrap_operand<Limit>::type(value))
+			{
+			}
+
+			dynamic_limit_data_t(const dynamic_limit_data_t&) = default;
+			dynamic_limit_data_t(dynamic_limit_data_t&&) = default;
+			dynamic_limit_data_t& operator=(const dynamic_limit_data_t&) = default;
+			dynamic_limit_data_t& operator=(dynamic_limit_data_t&&) = default;
+			~dynamic_limit_data_t() = default;
+
+			bool _initialized = false;
+			interpretable_t<Database> _value;
+		};
+
+	// DYNAMIC LIMIT
+	template<typename Database>
+		struct dynamic_limit_t
+		{
+			using _traits = make_traits<no_value_t, ::sqlpp::tag::limit>;
+			using _recursive_traits = make_recursive_traits<>;
+
+			// Data
+			using _data_t = dynamic_limit_data_t<Database>;
+
+			// Member implementation with data and methods
+			template <typename Policies>
+				struct _impl_t
+				{
+					template<typename Limit>
+						void set(Limit value)
+						{
+							// FIXME: Make sure that Limit does not require external tables? Need to read up on SQL
+							using arg_t = typename wrap_operand<Limit>::type;
+							_data._value = arg_t{value};
+							_data._initialized = true;
+						}
+				public:
+					_data_t _data;
+				};
+
+			// Member template for adding the named member to a statement
+			template<typename Policies>
+				struct _member_t
+				{
+					using _data_t = dynamic_limit_data_t<Database>;
+
+					_impl_t<Policies> limit;
+					_impl_t<Policies>& operator()() { return limit; }
+					const _impl_t<Policies>& operator()() const { return limit; }
+
+					template<typename T>
+						static auto _get_member(T t) -> decltype(t.limit)
+						{
+							return t.limit;
+						}
+				};
+
+			// Additional methods for the statement
+			template<typename Policies>
+				struct _methods_t
+				{
+					static void _check_consistency() {}
+				};
+		};
+
+	struct no_limit_t
+	{
+		using _traits = make_traits<no_value_t, ::sqlpp::tag::noop>;
+		using _recursive_traits = make_recursive_traits<>;
+
+		// Data
+		using _data_t = no_data_t;
+
+		// Member implementation with data and methods
+		template<typename Policies>
+			struct _impl_t
+			{
+				_data_t _data;
+			};
+
+		// Member template for adding the named member to a statement
+		template<typename Policies>
+			struct _member_t
+			{
+				using _data_t = no_data_t;
+
+				_impl_t<Policies> no_limit;
+				_impl_t<Policies>& operator()() { return no_limit; }
+				const _impl_t<Policies>& operator()() const { return no_limit; }
+
+				template<typename T>
+					static auto _get_member(T t) -> decltype(t.no_limit)
+					{
+						return t.no_limit;
+					}
+			};
+
+		template<typename Policies>
+			struct _methods_t
+			{
+				using _database_t = typename Policies::_database_t;
+				template<typename T>
+					using _new_statement_t = typename Policies::template _new_statement_t<no_limit_t, T>;
+
+				static void _check_consistency() {}
+
+				template<typename Arg>
+					auto limit(Arg arg)
+					-> _new_statement_t<limit_t<typename wrap_operand<Arg>::type>>
+					{
+						return { *static_cast<typename Policies::_statement_t*>(this), limit_data_t<typename wrap_operand<Arg>::type>{{arg}} };
+					}
+
+				auto dynamic_limit()
+					-> _new_statement_t<dynamic_limit_t<_database_t>>
+					{
+						static_assert(not std::is_same<_database_t, void>::value, "dynamic_limit must not be called in a static statement");
+						return { *static_cast<typename Policies::_statement_t*>(this), dynamic_limit_data_t<_database_t>{} };
+					}
+			};
+	};
+
+	// Interpreters
+	template<typename Context, typename Database>
+		struct serializer_t<Context, dynamic_limit_data_t<Database>>
+		{
+			using T = dynamic_limit_data_t<Database>;
+
+			static Context& _(const T& t, Context& context)
+			{
+				if (t._initialized)
+				{
+					context << " LIMIT ";
+					serialize(t._value, context);
+				}
+				return context;
+			}
+		};
+
+	template<typename Context, typename Limit>
+		struct serializer_t<Context, limit_data_t<Limit>>
+		{
+			using T = limit_data_t<Limit>;
+
+			static Context& _(const T& t, Context& context)
+			{
+				context << " LIMIT ";
+				serialize(t._value, context);
+				return context;
+			}
+		};
+}
+
+#endif

include/sqlpp11/max.h

@@ -31,67 +31,58 @@
 
 namespace sqlpp
 {
-	namespace vendor
+	template<typename Expr>
+		struct max_t: public value_type_of<Expr>::template expression_operators<max_t<Expr>>,
+		public alias_operators<max_t<Expr>>
 	{
-		template<typename Expr>
-		struct max_t: public Expr::_value_type::template expression_operators<max_t<Expr>>
+		using _traits = make_traits<value_type_of<Expr>, ::sqlpp::tag::expression, ::sqlpp::tag::named_expression>;
+		using _recursive_traits = make_recursive_traits<Expr>;
+
+		static_assert(is_expression_t<Expr>::value, "max() requires a value expression as argument");
+
+		struct _name_t
 		{
-			static_assert(is_value_t<Expr>::value, "max() requires a value expression as argument");
-
-			struct _value_type: public Expr::_value_type::_base_value_type
-			{
-				using _is_named_expression = std::true_type;
-			};
-
-			using _table_set = typename Expr::_table_set;
-
-			struct _name_t
-			{
-				static constexpr const char* _get_name() { return "MAX"; }
-				template<typename T>
-					struct _member_t
-					{
-						T max;
-						T& operator()() { return max; }
-						const T& operator()() const { return max; }
-					};
-			};
-
-			max_t(Expr expr):
-				_expr(expr)
-			{}
-
-			max_t(const max_t&) = default;
-			max_t(max_t&&) = default;
-			max_t& operator=(const max_t&) = default;
-			max_t& operator=(max_t&&) = default;
-			~max_t() = default;
-
-			Expr _expr;
-		};
-	}
-
-	namespace vendor
-	{
-		template<typename Context, typename Expr>
-			struct serializer_t<Context, vendor::max_t<Expr>>
-			{
-				using T = vendor::max_t<Expr>;
-
-				static Context& _(const T& t, Context& context)
+			static constexpr const char* _get_name() { return "MAX"; }
+			template<typename T>
+				struct _member_t
 				{
-					context << "MAX(";
-					serialize(t._expr, context);
-					context << ")";
-					return context;
-				}
-			};
-	}
+					T max;
+					T& operator()() { return max; }
+					const T& operator()() const { return max; }
+				};
+		};
+
+		max_t(Expr expr):
+			_expr(expr)
+		{}
+
+		max_t(const max_t&) = default;
+		max_t(max_t&&) = default;
+		max_t& operator=(const max_t&) = default;
+		max_t& operator=(max_t&&) = default;
+		~max_t() = default;
+
+		Expr _expr;
+	};
+
+	template<typename Context, typename Expr>
+		struct serializer_t<Context, max_t<Expr>>
+		{
+			using T = max_t<Expr>;
+
+			static Context& _(const T& t, Context& context)
+			{
+				context << "MAX(";
+				serialize(t._expr, context);
+				context << ")";
+				return context;
+			}
+		};
 
 	template<typename T>
-		auto max(T t) -> typename vendor::max_t<vendor::wrap_operand_t<T>>
+		auto max(T t) -> max_t<wrap_operand_t<T>>
 		{
-			static_assert(is_value_t<vendor::wrap_operand_t<T>>::value, "max() requires a value expression as argument");
+			static_assert(is_expression_t<wrap_operand_t<T>>::value, "max() requires a value expression as argument");
 			return { t };
 		}
 

include/sqlpp11/min.h

@@ -31,67 +31,58 @@
 
 namespace sqlpp
 {
-	namespace vendor
+	template<typename Expr>
+		struct min_t: public value_type_of<Expr>::template expression_operators<min_t<Expr>>,
+		public alias_operators<min_t<Expr>>
 	{
-		template<typename Expr>
-		struct min_t: public Expr::_value_type::template expression_operators<min_t<Expr>>
+		using _traits = make_traits<value_type_of<Expr>, ::sqlpp::tag::expression, ::sqlpp::tag::named_expression>;
+		using _recursive_traits = make_recursive_traits<Expr>;
+
+		static_assert(is_expression_t<Expr>::value, "min() requires a value expression as argument");
+
+		struct _name_t
 		{
-			static_assert(is_value_t<Expr>::value, "min() requires a value expression as argument");
-
-			struct _value_type: public Expr::_value_type::_base_value_type
-			{
-				using _is_named_expression = std::true_type;
-			};
-
-			using _table_set = typename Expr::_table_set;
-
-			struct _name_t
-			{
-				static constexpr const char* _get_name() { return "MIN"; }
-				template<typename T>
-					struct _member_t
-					{
-						T min;
-						T& operator()() { return min; }
-						const T& operator()() const { return min; }
-					};
-			};
-
-			min_t(Expr expr):
-				_expr(expr)
-			{}
-
-			min_t(const min_t&) = default;
-			min_t(min_t&&) = default;
-			min_t& operator=(const min_t&) = default;
-			min_t& operator=(min_t&&) = default;
-			~min_t() = default;
-
-			Expr _expr;
-		};
-	}
-
-	namespace vendor
-	{
-		template<typename Context, typename Expr>
-			struct serializer_t<Context, vendor::min_t<Expr>>
-			{
-				using T = vendor::min_t<Expr>;
-
-				static Context& _(const T& t, Context& context)
+			static constexpr const char* _get_name() { return "MIN"; }
+			template<typename T>
+				struct _member_t
 				{
-					context << "MIN(";
-					serialize(t._expr, context);
-					context << ")";
-					return context;
-				}
-			};
-	}
+					T min;
+					T& operator()() { return min; }
+					const T& operator()() const { return min; }
+				};
+		};
+
+		min_t(Expr expr):
+			_expr(expr)
+		{}
+
+		min_t(const min_t&) = default;
+		min_t(min_t&&) = default;
+		min_t& operator=(const min_t&) = default;
+		min_t& operator=(min_t&&) = default;
+		~min_t() = default;
+
+		Expr _expr;
+	};
+
+	template<typename Context, typename Expr>
+		struct serializer_t<Context, min_t<Expr>>
+		{
+			using T = min_t<Expr>;
+
+			static Context& _(const T& t, Context& context)
+			{
+				context << "MIN(";
+				serialize(t._expr, context);
+				context << ")";
+				return context;
+			}
+		};
 
 	template<typename T>
-		auto min(T t) -> typename vendor::min_t<vendor::wrap_operand_t<T>>
+		auto min(T t) -> min_t<wrap_operand_t<T>>
 		{
-			static_assert(is_value_t<vendor::wrap_operand_t<T>>::value, "min() requires a value expression as argument");
+			static_assert(is_expression_t<wrap_operand_t<T>>::value, "min() requires a value expression as argument");
 			return { t };
 		}
 

include/sqlpp11/multi_column.h

@@ -41,9 +41,10 @@ namespace sqlpp
 	template<typename Unused, typename... Columns>
 		struct multi_column_t
 		{
-			static_assert(detail::all_t<is_named_expression_t<Columns>::value...>::value, "multi_column parameters need to be named expressions");
+			using _traits = make_traits<no_value_t>;
+			using _recursive_traits = make_recursive_traits<Columns...>;
 
-			using _table_set = sqlpp::detail::make_joined_set_t<typename Columns::_table_set...>;
+			static_assert(detail::all_t<is_named_expression_t<Columns>::value...>::value, "multi_column parameters need to be named expressions");
 
 			multi_column_t(std::tuple<Columns...> columns):
 				_columns(columns)
@@ -75,10 +76,12 @@ namespace sqlpp
 	template<typename AliasProvider, typename... Columns>
 		struct multi_column_alias_t
 		{
+			using _traits = make_traits<no_value_t, tag::alias, tag::multi_column, tag::named_expression>;
+			using _recursive_traits = make_recursive_traits<Columns...>;
+
 			static_assert(detail::all_t<is_named_expression_t<Columns>::value...>::value, "multi_column parameters need to be named expressions");
 
 			using _name_t = typename AliasProvider::_name_t;
-			using _table_set = sqlpp::detail::make_joined_set_t<typename Columns::_table_set...>;
 
 			multi_column_alias_t(multi_column_t<void, Columns...> multi_column):
 				_columns(multi_column._columns)
@@ -107,31 +110,28 @@ namespace sqlpp
 			std::tuple<Columns...> _columns;
 		};
 
-	namespace vendor
-	{
-		template<typename Context, typename... Columns>
-			struct serializer_t<Context, multi_column_t<void, Columns...>>
+	template<typename Context, typename... Columns>
+		struct serializer_t<Context, multi_column_t<void, Columns...>>
+		{
+			using T = multi_column_t<void, Columns...>;
+
+			static void _(const T& t, Context& context)
 			{
-				using T = multi_column_t<void, Columns...>;
+				static_assert(wrong_t<Columns...>::value, "multi_column must be used with an alias");
+			}
+		};
 
-				static void _(const T& t, Context& context)
-				{
-					static_assert(wrong_t<Columns...>::value, "multi_column must be used with an alias");
-				}
-			};
+	template<typename Context, typename AliasProvider, typename... Columns>
+		struct serializer_t<Context, multi_column_alias_t<AliasProvider, Columns...>>
+		{
+			using T = multi_column_alias_t<AliasProvider, Columns...>;
 
-		template<typename Context, typename AliasProvider, typename... Columns>
-			struct serializer_t<Context, multi_column_alias_t<AliasProvider, Columns...>>
+			static Context& _(const T& t, Context& context)
 			{
-				using T = multi_column_alias_t<AliasProvider, Columns...>;
-
-				static Context& _(const T& t, Context& context)
-				{
-					interpret_tuple(t._columns, ',', context);
-					return context;
-				}
-			};
-	}
+				interpret_tuple(t._columns, ',', context);
+				return context;
+			}
+		};
 
 	namespace detail
 	{

include/sqlpp11/named_interpretable.h

@@ -0,0 +1,137 @@
+/*
+ * Copyright (c) 2013-2014, Roland Bock
+ * All rights reserved.
+ * 
+ * Redistribution and use in source and binary forms, with or without modification,
+ * are permitted provided that the following conditions are met:
+ * 
+ *   Redistributions of source code must retain the above copyright notice, this
+ *   list of conditions and the following disclaimer.
+ * 
+ *   Redistributions in binary form must reproduce the above copyright notice, this
+ *   list of conditions and the following disclaimer in the documentation and/or
+ *   other materials provided with the distribution.
+ * 
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR
+ * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+ * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef SQLPP_NAMED_SERIALIZABLE_H
+#define SQLPP_NAMED_SERIALIZABLE_H
+
+#include <memory>
+#include <sqlpp11/serializer_context.h>
+#include <sqlpp11/parameter_list.h>
+
+namespace sqlpp
+{
+	template<typename Db>
+		struct named_interpretable_t
+		{
+			using _serializer_context_t = typename Db::_serializer_context_t;
+			using _interpreter_context_t = typename Db::_interpreter_context_t;
+
+			template<typename T>
+				named_interpretable_t(T t):
+					_impl(std::make_shared<_impl_t<T>>(t))
+			{}
+
+			named_interpretable_t(const named_interpretable_t&) = default;
+			named_interpretable_t(named_interpretable_t&&) = default;
+			named_interpretable_t& operator=(const named_interpretable_t&) = default;
+			named_interpretable_t& operator=(named_interpretable_t&&) = default;
+			~named_interpretable_t() = default;
+
+			sqlpp::serializer_context_t& serialize(sqlpp::serializer_context_t& context) const
+			{
+				return _impl->serialize(context);
+			}
+
+			// This method only exists if Db::_serializer_context_t and sqlpp::serializer_context_t are not the same
+			template<typename Context>
+				auto serialize(Context& context) const
+				-> typename std::enable_if<std::is_same<Context, _serializer_context_t>::value 
+				and not std::is_same<Context, sqlpp::serializer_context_t>::value, Context&>::type
+				{
+					return _impl->db_serialize(context);
+				}
+
+			_interpreter_context_t& interpret(_interpreter_context_t& context) const
+			{
+				return _impl->interpret(context);
+			}
+
+			std::string _get_name() const
+			{
+				return _impl->_get_name();
+			}
+
+		private:
+			struct _impl_base
+			{
+				virtual sqlpp::serializer_context_t& serialize(sqlpp::serializer_context_t& context) const = 0;
+				virtual _serializer_context_t& db_serialize(_serializer_context_t& context) const = 0;
+				virtual _interpreter_context_t& interpret(_interpreter_context_t& context) const = 0;
+				virtual std::string _get_name() const = 0;
+			};
+
+			template<typename T>
+				struct _impl_t: public _impl_base
+			{
+				static_assert(not make_parameter_list_t<T>::size::value, "parameters not supported in dynamic statement parts");
+				_impl_t(T t):
+					_t(t)
+				{}
+
+				sqlpp::serializer_context_t& serialize(sqlpp::serializer_context_t& context) const
+				{
+					sqlpp::serialize(_t, context);
+					return context;
+				}
+
+				_serializer_context_t& db_serialize(_serializer_context_t& context) const
+				{
+					Db::_serialize_interpretable(_t, context);
+					return context;
+				}
+
+				_interpreter_context_t& interpret(_interpreter_context_t& context) const
+				{
+					Db::_interpret_interpretable(_t, context);
+					return context;
+				}
+
+				std::string _get_name() const
+				{
+					return T::_name_t::_get_name();
+				}
+
+				T _t;
+			};
+
+			std::shared_ptr<const _impl_base> _impl;
+		};
+
+	template<typename Context, typename Database>
+		struct serializer_t<Context, named_interpretable_t<Database>>
+		{
+			using T = named_interpretable_t<Database>;
+
+			static Context& _(const T& t, Context& context)
+			{
+				t.serialize(context);
+				return context;
+			}
+		};
+
+}
+
+#endif

include/sqlpp11/no_data.h

@@ -24,21 +24,25 @@
  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
-#ifndef SQLPP_CHAR_RESULT_ROW_H
-#define SQLPP_CHAR_RESULT_ROW_H
+#ifndef SQLPP_NO_DATA_H
+#define SQLPP_NO_DATA_H
+
+#include <type_traits>
+#include <sqlpp11/serializer.h>
 
 namespace sqlpp
 {
-	struct char_result_row_t
-	{
-		const char** data;
-		size_t* len;
+	struct no_data_t {};
 
-		bool operator==(const char_result_row_t& rhs) const
+	template<typename Context>
+		struct serializer_t<Context, no_data_t>
 		{
-			return data == rhs.data and len == rhs.len; 
-		}
-	};
-}
+			using T = no_data_t;
 
+			static Context& _(const T& t, Context& context)
+			{
+				return context;
+			}
+		};
+}
 #endif

include/sqlpp11/no_value.h

@@ -33,11 +33,7 @@ namespace sqlpp
 {
 	struct no_value_t
 	{
-		template<typename T>
-			using _constraint = std::false_type;
-
-		using _base_value_type = no_value_t;
-
+		using _tag = void;
 		template<typename T>
 			struct _is_valid_operand
 			{

include/sqlpp11/noop.h

@@ -28,30 +28,36 @@
 #define SQLPP_NOOP_H
 
 #include <type_traits>
+#include <sqlpp11/no_value.h>
+#include <sqlpp11/serializer.h>
 
 namespace sqlpp
 {
-	namespace vendor
+	struct noop 
 	{
-		struct noop 
+		using _traits = make_traits<no_value_t, ::sqlpp::tag::noop>;
+		using _recursive_traits = make_recursive_traits<>;
+
+		struct _name_t {};
+
+		template<typename Policies>
+			struct _result_methods_t
+			{};
+	};
+
+	template<typename Context>
+		struct serializer_t<Context, noop>
 		{
-			using is_noop = std::true_type;
+			using T = noop;
+
+			static Context& _(const T& t, Context& context)
+			{
+				return context;
+			}
 		};
 
-		template<typename Context>
-			struct serializer_t<Context, noop>
-			{
-				using T = noop;
-
-				static Context& _(const T& t, Context& context)
-				{
-					return context;
-				}
-			};
-
-		template<typename T>
-			struct is_noop: std::is_same<T, noop> {};
-	}
+	template<typename T>
+		struct is_noop: std::is_same<T, noop> {};
 
 }
 #endif

include/sqlpp11/noop_fwd.h

@@ -29,12 +29,9 @@
 
 namespace sqlpp
 {
-	namespace vendor
-	{
-		struct noop;
+	struct noop;
 
-		template<typename T>
-			struct is_noop;
-	}
+	template<typename T>
+		struct is_noop;
 }
 #endif

include/sqlpp11/null.h

@@ -33,25 +33,21 @@ namespace sqlpp
 {
 	struct null_t
 	{
-		static constexpr bool _is_expression = true;
-		using _value_type = no_value_t;
-		using _table_set = ::sqlpp::detail::type_set<>;
+		using _traits = make_traits<no_value_t, tag::expression>;
+		using _recursive_traits = make_recursive_traits<>;
 	};
 
-	namespace vendor
-	{
-		template<typename Context>
-			struct serializer_t<Context, null_t>
-			{
-				using Operand = null_t;
+	template<typename Context>
+		struct serializer_t<Context, null_t>
+		{
+			using Operand = null_t;
 
-				static Context& _(const Operand& t, Context& context)
-				{
-					context << "NULL";
-					return context;
-				}
-			};
-	}
+			static Context& _(const Operand& t, Context& context)
+			{
+				context << "NULL";
+				return context;
+			}
+		};
 
 	constexpr null_t null = {};
 

include/sqlpp11/offset.h

@@ -0,0 +1,272 @@
+/*
+ * Copyright (c) 2013-2014, Roland Bock
+ * All rights reserved.
+ * 
+ * Redistribution and use in source and binary forms, with or without modification,
+ * are permitted provided that the following conditions are met:
+ * 
+ *   Redistributions of source code must retain the above copyright notice, this
+ *   list of conditions and the following disclaimer.
+ * 
+ *   Redistributions in binary form must reproduce the above copyright notice, this
+ *   list of conditions and the following disclaimer in the documentation and/or
+ *   other materials provided with the distribution.
+ * 
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR
+ * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+ * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef SQLPP_OFFSET_H
+#define SQLPP_OFFSET_H
+
+#include <sqlpp11/type_traits.h>
+#include <sqlpp11/policy_update.h>
+#include <sqlpp11/detail/type_set.h>
+
+namespace sqlpp
+{
+	// OFFSET DATA
+	template<typename Offset>
+		struct offset_data_t
+		{
+			offset_data_t(Offset value):
+				_value(value)
+			{}
+
+			offset_data_t(const offset_data_t&) = default;
+			offset_data_t(offset_data_t&&) = default;
+			offset_data_t& operator=(const offset_data_t&) = default;
+			offset_data_t& operator=(offset_data_t&&) = default;
+			~offset_data_t() = default;
+
+			Offset _value;
+		};
+
+	// OFFSET
+	template<typename Offset>
+		struct offset_t
+		{
+			using _traits = make_traits<no_value_t, ::sqlpp::tag::offset>;
+			using _recursive_traits = make_recursive_traits<Offset>;
+
+			static_assert(is_integral_t<Offset>::value, "offset requires an integral value or integral parameter");
+
+			// Data
+			using _data_t = offset_data_t<Offset>;
+
+			// Member implementation with data and methods
+			template <typename Policies>
+				struct _impl_t
+				{
+					_data_t _data;
+				};
+
+			// Member template for adding the named member to a statement
+			template<typename Policies>
+				struct _member_t
+				{
+					using _data_t = offset_data_t<Offset>;
+
+					_impl_t<Policies> offset;
+					_impl_t<Policies>& operator()() { return offset; }
+					const _impl_t<Policies>& operator()() const { return offset; }
+
+					template<typename T>
+						static auto _get_member(T t) -> decltype(t.offset)
+						{
+							return t.offset;
+						}
+				};
+
+			template<typename Policies>
+				struct _methods_t
+				{
+					static void _check_consistency() {}
+				};
+		};
+
+	// DYNAMIC OFFSET DATA
+	template<typename Database>
+		struct dynamic_offset_data_t
+		{
+			dynamic_offset_data_t():
+				_value(noop())
+			{
+			}
+
+			template<typename Offset>
+				dynamic_offset_data_t(Offset value):
+					_initialized(true),
+					_value(typename wrap_operand<Offset>::type(value))
+			{
+			}
+
+			dynamic_offset_data_t(const dynamic_offset_data_t&) = default;
+			dynamic_offset_data_t(dynamic_offset_data_t&&) = default;
+			dynamic_offset_data_t& operator=(const dynamic_offset_data_t&) = default;
+			dynamic_offset_data_t& operator=(dynamic_offset_data_t&&) = default;
+			~dynamic_offset_data_t() = default;
+
+			bool _initialized = false;
+			interpretable_t<Database> _value;
+		};
+
+	// DYNAMIC OFFSET
+	template<typename Database>
+		struct dynamic_offset_t
+		{
+			using _traits = make_traits<no_value_t, ::sqlpp::tag::offset>;
+			using _recursive_traits = make_recursive_traits<>;
+
+			// Data
+			using _data_t = dynamic_offset_data_t<Database>;
+
+			// Member implementation with data and methods
+			template <typename Policies>
+				struct _impl_t
+				{
+					template<typename Offset>
+						void set(Offset value)
+						{
+							// FIXME: Make sure that Offset does not require external tables? Need to read up on SQL
+							using arg_t = typename wrap_operand<Offset>::type;
+							_data._value = arg_t{value};
+							_data._initialized = true;
+						}
+				public:
+					_data_t _data;
+				};
+
+			// Member template for adding the named member to a statement
+			template<typename Policies>
+				struct _member_t
+				{
+					using _data_t = dynamic_offset_data_t<Database>;
+
+					_impl_t<Policies> offset;
+					_impl_t<Policies>& operator()() { return offset; }
+					const _impl_t<Policies>& operator()() const { return offset; }
+
+					template<typename T>
+						static auto _get_member(T t) -> decltype(t.offset)
+						{
+							return t.offset;
+						}
+				};
+
+			template<typename Policies>
+				struct _methods_t
+				{
+					static void _check_consistency() {}
+
+					template<typename Offset>
+						void set_offset(Offset value)
+						{
+							// FIXME: Make sure that Offset does not require external tables? Need to read up on SQL
+							using arg_t = typename wrap_operand<Offset>::type;
+							static_cast<typename Policies::_statement_t*>(this)->_offset()._value = arg_t{value};
+							static_cast<typename Policies::_statement_t*>(this)->_offset()._initialized = true;
+						}
+				};
+
+			bool _initialized = false;
+			interpretable_t<Database> _value;
+		};
+
+	struct no_offset_t
+	{
+		using _traits = make_traits<no_value_t, ::sqlpp::tag::noop>;
+		using _recursive_traits = make_recursive_traits<>;
+
+		// Data
+		using _data_t = no_data_t;
+
+		// Member implementation with data and methods
+		template<typename Policies>
+			struct _impl_t
+			{
+				_data_t _data;
+			};
+
+		// Member template for adding the named member to a statement
+		template<typename Policies>
+			struct _member_t
+			{
+				using _data_t = no_data_t;
+
+				_impl_t<Policies> no_offset;
+				_impl_t<Policies>& operator()() { return no_offset; }
+				const _impl_t<Policies>& operator()() const { return no_offset; }
+
+				template<typename T>
+					static auto _get_member(T t) -> decltype(t.no_offset)
+					{
+						return t.no_offset;
+					}
+			};
+
+		template<typename Policies>
+			struct _methods_t
+			{
+				using _database_t = typename Policies::_database_t;
+				template<typename T>
+					using _new_statement_t = typename Policies::template _new_statement_t<no_offset_t, T>;
+
+				static void _check_consistency() {}
+
+				template<typename Arg>
+					auto offset(Arg arg)
+					-> _new_statement_t<offset_t<typename wrap_operand<Arg>::type>>
+					{
+						return { *static_cast<typename Policies::_statement_t*>(this), offset_data_t<typename wrap_operand<Arg>::type>{{arg}} };
+					}
+
+				auto dynamic_offset()
+					-> _new_statement_t<dynamic_offset_t<_database_t>>
+					{
+						static_assert(not std::is_same<_database_t, void>::value, "dynamic_offset must not be called in a static statement");
+						return { *static_cast<typename Policies::_statement_t*>(this), dynamic_offset_data_t<_database_t>{} };
+					}
+			};
+	};
+
+	// Interpreters
+	template<typename Context, typename Offset>
+		struct serializer_t<Context, offset_data_t<Offset>>
+		{
+			using T = offset_data_t<Offset>;
+
+			static Context& _(const T& t, Context& context)
+			{
+				context << " OFFSET ";
+				serialize(t._value, context);
+				return context;
+			}
+		};
+
+	template<typename Context, typename Database>
+		struct serializer_t<Context, dynamic_offset_data_t<Database>>
+		{
+			using T = dynamic_offset_data_t<Database>;
+
+			static Context& _(const T& t, Context& context)
+			{
+				if (t._initialized)
+				{
+					context << " OFFSET ";
+					serialize(t._value, context);
+				}
+				return context;
+			}
+		};
+}
+
+#endif

include/sqlpp11/on.h

@@ -28,8 +28,8 @@
 #define SQLPP_ON_H
 
 #include <sqlpp11/type_traits.h>
-#include <sqlpp11/vendor/interpret_tuple.h>
-#include <sqlpp11/vendor/interpretable_list.h>
+#include <sqlpp11/interpret_tuple.h>
+#include <sqlpp11/interpretable_list.h>
 #include <sqlpp11/detail/logic.h>
 
 namespace sqlpp
@@ -37,8 +37,10 @@ namespace sqlpp
 	template<typename Database, typename... Expr>
 		struct on_t
 		{
-			using _is_on = std::true_type;
-			using _is_dynamic = typename std::conditional<std::is_same<Database, void>::value, std::false_type, std::true_type>::type;
+			using _traits = make_traits<no_value_t, tag::on>;
+			using _recursive_traits = make_recursive_traits<Expr...>;
+
+			using _is_dynamic = is_database<Database>;
 
 			static_assert(_is_dynamic::value or sizeof...(Expr), "at least one expression argument required in on()");
 			static_assert(detail::all_t<is_expression_t<Expr>::value...>::value, "at least one argument is not an expression in on()");
@@ -51,30 +53,27 @@ namespace sqlpp
 				}
 
 			std::tuple<Expr...> _expressions;
-			vendor::interpretable_list_t<Database> _dynamic_expressions;
+			interpretable_list_t<Database> _dynamic_expressions;
 		};
 
-	namespace vendor
-	{
-		template<typename Context, typename Database, typename... Expr>
-			struct serializer_t<Context, on_t<Database, Expr...>>
+	template<typename Context, typename Database, typename... Expr>
+		struct serializer_t<Context, on_t<Database, Expr...>>
+		{
+			using T = on_t<Database, Expr...>;
+
+			static Context& _(const T& t, Context& context)
 			{
-				using T = on_t<Database, Expr...>;
-
-				static Context& _(const T& t, Context& context)
-				{
-					if (sizeof...(Expr) == 0 and t._dynamic_expressions.empty())
-						return context;
-					context << " ON ";
-					interpret_tuple(t._expressions, " AND ", context);
-					if (sizeof...(Expr) and not t._dynamic_expressions.empty())
-						context << " AND ";
-					interpret_list(t._dynamic_expressions, " AND ", context);
+				if (sizeof...(Expr) == 0 and t._dynamic_expressions.empty())
 					return context;
-				}
-			};
+				context << " ON ";
+				interpret_tuple(t._expressions, " AND ", context);
+				if (sizeof...(Expr) and not t._dynamic_expressions.empty())
+					context << " AND ";
+				interpret_list(t._dynamic_expressions, " AND ", context);
+				return context;
+			}
+		};
 
-	}
 }
 
 #endif

include/sqlpp11/order_by.h

@@ -0,0 +1,214 @@
+/*
+ * Copyright (c) 2013-2014, Roland Bock
+ * All rights reserved.
+ * 
+ * Redistribution and use in source and binary forms, with or without modification,
+ * are permitted provided that the following conditions are met:
+ * 
+ *   Redistributions of source code must retain the above copyright notice, this
+ *   list of conditions and the following disclaimer.
+ * 
+ *   Redistributions in binary form must reproduce the above copyright notice, this
+ *   list of conditions and the following disclaimer in the documentation and/or
+ *   other materials provided with the distribution.
+ * 
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR
+ * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+ * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef SQLPP_ORDER_BY_H
+#define SQLPP_ORDER_BY_H
+
+#include <tuple>
+#include <sqlpp11/type_traits.h>
+#include <sqlpp11/interpret_tuple.h>
+#include <sqlpp11/interpretable.h>
+#include <sqlpp11/policy_update.h>
+#include <sqlpp11/detail/logic.h>
+#include <sqlpp11/detail/type_set.h>
+
+namespace sqlpp
+{
+	// ORDER BY DATA
+	template<typename Database, typename... Expressions>
+		struct order_by_data_t
+		{
+			order_by_data_t(Expressions... expressions):
+				_expressions(expressions...)
+			{}
+
+			order_by_data_t(const order_by_data_t&) = default;
+			order_by_data_t(order_by_data_t&&) = default;
+			order_by_data_t& operator=(const order_by_data_t&) = default;
+			order_by_data_t& operator=(order_by_data_t&&) = default;
+			~order_by_data_t() = default;
+
+			std::tuple<Expressions...> _expressions;
+			interpretable_list_t<Database> _dynamic_expressions;
+		};
+
+	// ORDER BY
+	template<typename Database, typename... Expressions>
+		struct order_by_t
+		{
+			using _traits = make_traits<no_value_t, ::sqlpp::tag::order_by>;
+			using _recursive_traits = make_recursive_traits<Expressions...>;
+
+			using _is_dynamic = is_database<Database>;
+
+			static_assert(_is_dynamic::value or sizeof...(Expressions), "at least one expression (e.g. a column) required in order_by()");
+
+			static_assert(not ::sqlpp::detail::has_duplicates<Expressions...>::value, "at least one duplicate argument detected in order_by()");
+
+			static_assert(::sqlpp::detail::all_t<is_expression_t<Expressions>::value...>::value, "at least one argument is not an expression in order_by()");
+
+			// Data
+			using _data_t = order_by_data_t<Database, Expressions...>;
+
+			// Member implementation with data and methods
+			template<typename Policies>
+				struct _impl_t
+				{
+					template<typename Expression>
+						void add_ntc(Expression expression)
+						{
+							add<Expression, std::false_type>(expression);
+						}
+
+					template<typename Expression, typename TableCheckRequired = std::true_type>
+						void add(Expression expression)
+						{
+							static_assert(_is_dynamic::value, "add() must not be called for static order_by");
+							static_assert(is_expression_t<Expression>::value, "invalid expression argument in order_by::add()");
+							static_assert(TableCheckRequired::value or Policies::template _no_unknown_tables<Expression>::value, "expression uses tables unknown to this statement in order_by::add()");
+
+							using ok = ::sqlpp::detail::all_t<_is_dynamic::value, is_expression_t<Expression>::value>;
+
+							_add_impl(expression, ok()); // dispatch to prevent compile messages after the static_assert
+						}
+
+				private:
+					template<typename Expression>
+						void _add_impl(Expression expression, const std::true_type&)
+						{
+							return _data._dynamic_expressions.emplace_back(expression);
+						}
+
+					template<typename Expression>
+						void _add_impl(Expression expression, const std::false_type&);
+				public:
+					_data_t _data;
+				};
+
+			// Member template for adding the named member to a statement
+			template<typename Policies>
+				struct _member_t
+				{
+					using _data_t = order_by_data_t<Database, Expressions...>;
+
+					_impl_t<Policies> order_by;
+					_impl_t<Policies>& operator()() { return order_by; }
+					const _impl_t<Policies>& operator()() const { return order_by; }
+
+					template<typename T>
+						static auto _get_member(T t) -> decltype(t.order_by)
+						{
+							return t.order_by;
+						}
+				};
+
+			template<typename Policies>
+				struct _methods_t
+				{
+					static void _check_consistency() {}
+				};
+		};
+
+	// NO ORDER BY YET
+	struct no_order_by_t
+	{
+		using _traits = make_traits<no_value_t, ::sqlpp::tag::noop>;
+		using _recursive_traits = make_recursive_traits<>;
+
+		// Data
+		using _data_t = no_data_t;
+
+		// Member implementation with data and methods
+		template<typename Policies>
+			struct _impl_t
+			{
+				_data_t _data;
+			};
+
+		// Member template for adding the named member to a statement
+		template<typename Policies>
+			struct _member_t
+			{
+				using _data_t = no_data_t;
+
+				_impl_t<Policies> no_order_by;
+				_impl_t<Policies>& operator()() { return no_order_by; }
+				const _impl_t<Policies>& operator()() const { return no_order_by; }
+
+				template<typename T>
+					static auto _get_member(T t) -> decltype(t.no_order_by)
+					{
+						return t.no_order_by;
+					}
+			};
+
+		template<typename Policies>
+			struct _methods_t
+			{
+				using _database_t = typename Policies::_database_t;
+				template<typename T>
+					using _new_statement_t = typename Policies::template _new_statement_t<no_order_by_t, T>;
+
+				static void _check_consistency() {}
+
+				template<typename... Args>
+					auto order_by(Args... args)
+					-> _new_statement_t<order_by_t<void, Args...>>
+					{
+						return { *static_cast<typename Policies::_statement_t*>(this), order_by_data_t<void, Args...>{args...} };
+					}
+
+				template<typename... Args>
+					auto dynamic_order_by(Args... args)
+					-> _new_statement_t<order_by_t<_database_t, Args...>>
+					{
+						static_assert(not std::is_same<_database_t, void>::value, "dynamic_order_by must not be called in a static statement");
+						return { *static_cast<typename Policies::_statement_t*>(this), order_by_data_t<_database_t, Args...>{args...} };
+					}
+			};
+	};
+
+	// Interpreters
+	template<typename Context, typename Database, typename... Expressions>
+		struct serializer_t<Context, order_by_data_t<Database, Expressions...>>
+		{
+			using T = order_by_data_t<Database, Expressions...>;
+
+			static Context& _(const T& t, Context& context)
+			{
+				if (sizeof...(Expressions) == 0 and t._dynamic_expressions.empty())
+					return context;
+				context << " ORDER BY ";
+				interpret_tuple(t._expressions, ',', context);
+				if (sizeof...(Expressions) and not t._dynamic_expressions.empty())
+					context << ',';
+				interpret_list(t._dynamic_expressions, ',', context);
+				return context;
+			}
+		};
+}
+
+#endif

include/sqlpp11/parameter.h

@@ -34,16 +34,18 @@
 namespace sqlpp
 {
 	template<typename ValueType, typename NameType>
-	struct parameter_t: public ValueType::template expression_operators<parameter_t<ValueType, NameType>>
+		struct parameter_t: public ValueType::template expression_operators<parameter_t<ValueType, NameType>>
 	{
-		struct _value_type: public ValueType
+		using _traits = make_traits<ValueType, tag::parameter, tag::expression>;
+		struct _recursive_traits
 		{
-			using _is_expression = std::true_type;
-			using _is_alias = std::false_type;
+			using _parameters = std::tuple<parameter_t>;
+			using _provided_tables = detail::type_set<>;
+			using _required_tables = detail::type_set<>;
+			using _extra_tables = detail::type_set<>;
 		};
-		using _is_parameter = std::true_type;
+
 		using _instance_t = typename NameType::_name_t::template _member_t<typename ValueType::_parameter_t>;
-		using _table_set = sqlpp::detail::type_set<>;
 
 		parameter_t()
 		{}
@@ -55,24 +57,21 @@ namespace sqlpp
 		~parameter_t() = default;
 	};
 
-	namespace vendor
-	{
-		template<typename Context, typename ValueType, typename NameType>
-			struct serializer_t<Context, parameter_t<ValueType, NameType>>
-			{
-				using T = parameter_t<ValueType, NameType>;
+	template<typename Context, typename ValueType, typename NameType>
+		struct serializer_t<Context, parameter_t<ValueType, NameType>>
+		{
+			using T = parameter_t<ValueType, NameType>;
 
-				static Context& _(const T& t, Context& context)
-				{
-					context << "?";
-					return context;
-				}
-			};
-	}
+			static Context& _(const T& t, Context& context)
+			{
+				context << "?";
+				return context;
+			}
+		};
 
 	template<typename NamedExpr>
 		auto parameter(const NamedExpr&)
-		-> parameter_t<typename NamedExpr::_value_type, NamedExpr>
+		-> parameter_t<value_type_of<NamedExpr>, NamedExpr>
 		{
 			static_assert(is_named_expression_t<NamedExpr>::value, "not a named expression");
 			return {};
@@ -80,9 +79,9 @@ namespace sqlpp
 
 	template<typename ValueType, typename AliasProvider>
 		auto parameter(const ValueType&, const AliasProvider&)
-		-> parameter_t<ValueType, AliasProvider>
+		-> parameter_t<wrap_operand_t<ValueType>, AliasProvider>
 		{
-			static_assert(is_value_t<ValueType>::value, "first argument is not a value type");
+			static_assert(is_expression_t<ValueType>::value, "first argument is not a value type");
 			static_assert(is_alias_provider_t<AliasProvider>::value, "second argument is not an alias provider");
 			return {};
 		}

include/sqlpp11/parameter_list.h

@@ -28,7 +28,8 @@
 #define SQLPP_PARAMETER_LIST_H
 
 #include <tuple>
-#include <sqlpp11/vendor/wrong.h>
+#include <sqlpp11/type_traits.h>
+#include <sqlpp11/wrong.h>
 #include <sqlpp11/detail/index_sequence.h>
 
 namespace sqlpp
@@ -36,7 +37,7 @@ namespace sqlpp
 	template<typename T>
 		struct parameter_list_t
 		{
-			static_assert(vendor::wrong_t<T>::value, "Template parameter for parameter_list_t has to be a tuple");
+			static_assert(wrong_t<T>::value, "Template parameter for parameter_list_t has to be a tuple");
 		};
 
 	template<typename... Parameter>
@@ -63,40 +64,8 @@ namespace sqlpp
 				}
 		};
 
-	namespace detail
-	{
-		template<typename Exp, typename Enable = void>
-			struct get_parameter_tuple
-			{
-				using type = std::tuple<>;
-			};
-
-		template<typename Exp>
-			struct get_parameter_tuple<Exp, typename std::enable_if<is_parameter_t<Exp>::value, void>::type>
-			{
-				using type = std::tuple<Exp>;
-			};
-
-		template<typename... Param>
-			struct get_parameter_tuple<std::tuple<Param...>, void>
-			{
-				// cat together parameter tuples
-				using type = decltype(std::tuple_cat(std::declval<typename get_parameter_tuple<Param>::type>()...));
-			};
-
-		template<typename Exp>
-			struct get_parameter_tuple<Exp, typename std::enable_if<not std::is_same<typename Exp::_parameter_tuple_t, void>::value, void>::type>
-			{
-				using type = typename get_parameter_tuple<typename Exp::_parameter_tuple_t>::type;
-			};
-
-	}
-
 	template<typename Exp>
-		struct make_parameter_list_t
-		{
-			using type = parameter_list_t<typename detail::get_parameter_tuple<Exp>::type>;
-		};
+		using make_parameter_list_t = parameter_list_t<parameters_of<Exp>>;
 
 }
 

include/sqlpp11/policy_update.h

@@ -0,0 +1,56 @@
+/*
+ * Copyright (c) 2013-2014, Roland Bock
+ * All rights reserved.
+ * 
+ * Redistribution and use in source and binary forms, with or without modification,
+ * are permitted provided that the following conditions are met:
+ * 
+ *   Redistributions of source code must retain the above copyright notice, this
+ *   list of conditions and the following disclaimer.
+ * 
+ *   Redistributions in binary form must reproduce the above copyright notice, this
+ *   list of conditions and the following disclaimer in the documentation and/or
+ *   other materials provided with the distribution.
+ * 
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR
+ * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+ * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef SQLPP_POLICY_UPDATE_H
+#define SQLPP_POLICY_UPDATE_H
+
+#include <sqlpp11/wrong.h>
+
+namespace sqlpp
+{
+	template<typename Needle, typename Replacement>
+		struct policy_update_impl
+		{
+			template<typename T>
+				using _policy_t = typename std::conditional<std::is_same<Needle, T>::value, Replacement, T>::type;
+		};
+
+	template<typename T, typename Needle, typename Replacement>
+		using policy_update_t = typename policy_update_impl<Needle, Replacement>::template _policy_t<T>;
+
+	template<typename Original, typename Needle, typename Replacement>
+		struct update_policies_impl
+		{
+			using type = typename Original::template _policy_update_t<Needle, Replacement>;
+		};
+
+	template<typename Original, typename Needle, typename Replacement>
+		using update_policies_t = typename update_policies_impl<Original, Needle, Replacement>::type;
+
+
+}
+
+#endif

include/sqlpp11/prepared_insert.h

@@ -35,14 +35,14 @@ namespace sqlpp
 	template<typename Db, typename Insert>
 		struct prepared_insert_t
 		{
-			using _parameter_list_t = typename Insert::_parameter_list_t;
+			using _parameter_list_t = make_parameter_list_t<Insert>;
 			using _prepared_statement_t = typename Db::_prepared_statement_t;
 
 			auto _run(Db& db) const
 				-> size_t
-			{
-				return db.run_prepared_insert(*this);
-			}
+				{
+					return db.run_prepared_insert(*this);
+				}
 
 			void _bind_params() const
 			{

include/sqlpp11/prepared_remove.h

@@ -35,14 +35,14 @@ namespace sqlpp
 	template<typename Db, typename Remove>
 		struct prepared_remove_t
 		{
-			using _parameter_list_t = typename Remove::_parameter_list_t;
+			using _parameter_list_t = make_parameter_list_t<Remove>;
 			using _prepared_statement_t = typename Db::_prepared_statement_t;
 
 			auto _run(Db& db) const
 				-> size_t
-			{
-				return db.run_prepared_insert(*this);
-			}
+				{
+					return db.run_prepared_insert(*this);
+				}
 
 			void _bind_params() const
 			{

include/sqlpp11/prepared_select.h

@@ -36,15 +36,15 @@ namespace sqlpp
 		struct prepared_select_t
 		{
 			using _result_row_t = typename Select::template _result_row_t<Database>;
-			using _parameter_list_t = typename Select::_parameter_list_t;
+			using _parameter_list_t = make_parameter_list_t<Select>;
 			using _dynamic_names_t = typename Select::_dynamic_names_t;
 			using _prepared_statement_t = typename Database::_prepared_statement_t;
 
 			auto _run(Database& db) const
 				-> result_t<decltype(db.run_prepared_select(*this)), _result_row_t>
-			{
-				return {db.run_prepared_select(*this), _dynamic_names};
-			}
+				{
+					return {db.run_prepared_select(*this), _dynamic_names};
+				}
 
 			void _bind_params() const
 			{

include/sqlpp11/prepared_update.h

@@ -35,14 +35,14 @@ namespace sqlpp
 	template<typename Db, typename Update>
 		struct prepared_update_t
 		{
-			using _parameter_list_t = typename Update::_parameter_list_t;
+			using _parameter_list_t = make_parameter_list_t<Update>;
 			using _prepared_statement_t = typename Db::_prepared_statement_t;
 
 			auto _run(Db& db) const
 				-> size_t
-			{
-				return db.run_prepared_insert(*this);
-			}
+				{
+					return db.run_prepared_insert(*this);
+				}
 
 			void _bind_params() const
 			{

include/sqlpp11/remove.h

@@ -27,183 +27,103 @@
 #ifndef SQLPP_REMOVE_H
 #define SQLPP_REMOVE_H
 
+#include <sqlpp11/statement.h>
 #include <sqlpp11/type_traits.h>
 #include <sqlpp11/parameter_list.h>
 #include <sqlpp11/prepared_remove.h>
-#include <sqlpp11/vendor/noop.h>
-#include <sqlpp11/vendor/single_table.h>
-#include <sqlpp11/vendor/extra_tables.h>
-#include <sqlpp11/vendor/using.h>
-#include <sqlpp11/vendor/where.h>
-#include <sqlpp11/vendor/policy_update.h>
-#include <sqlpp11/detail/arg_selector.h>
+#include <sqlpp11/noop.h>
+#include <sqlpp11/from.h>
+#include <sqlpp11/extra_tables.h>
+#include <sqlpp11/using.h>
+#include <sqlpp11/where.h>
 
 namespace sqlpp
 {
-	template<typename Db,
-			typename... Policies
-				>
-		struct remove_t;
-
-	namespace detail
+	struct remove_name_t {};
+	struct remove_t: public statement_name_t<remove_name_t>
 	{
-		template<typename Db = void,
-			typename Table = vendor::no_single_table_t,
-			typename Using = vendor::no_using_t,
-			typename ExtraTables = vendor::no_extra_tables_t,
-			typename Where = vendor::no_where_t
-				>
-			struct remove_policies_t 
+		using _traits = make_traits<no_value_t, tag::return_value>;
+		struct _name_t {};
+
+		template<typename Policies>
+			struct _result_methods_t
 			{
-				using _database_t = Db;
-				using _table_t = Table;
-				using _using_t = Using;
-				using _extra_tables_t = ExtraTables;
-				using _where_t = Where;
+				using _statement_t = typename Policies::_statement_t;
 
-				using _statement_t = remove_t<Db, Table, Using, ExtraTables, Where>;
+				const _statement_t& _get_statement() const
+				{
+					return static_cast<const _statement_t&>(*this);
+				}
 
-				struct _methods_t:
-					public _using_t::template _methods_t<remove_policies_t>,
-					public _extra_tables_t::template _methods_t<remove_policies_t>,
-					public _where_t::template _methods_t<remove_policies_t>
-				{};
-
-				template<typename Needle, typename Replacement, typename... Policies>
-					struct _policies_update_t
+				template<typename Db>
+					auto _run(Db& db) const -> decltype(db.remove(this->_get_statement()))
 					{
-						using type =  remove_t<Db, vendor::policy_update_t<Policies, Needle, Replacement>...>;
-					};
+						_statement_t::_check_consistency();
 
-				template<typename Needle, typename Replacement>
-					using _new_statement_t = typename _policies_update_t<Needle, Replacement, Table, Using, ExtraTables, Where>::type;
+						static_assert(_statement_t::_get_static_no_of_parameters() == 0, "cannot run remove directly with parameters, use prepare instead");
+						return db.remove(_get_statement());
+					}
 
-				using _known_tables = detail::make_joined_set_t<typename _table_t::_table_set, typename _using_t::_table_set, typename _extra_tables_t::_table_set>;
+					 template<typename Db>
+					 auto _prepare(Db& db) const
+					 -> prepared_remove_t<Db, _statement_t>
+					 {
+						 _statement_t::_check_consistency();
 
-				template<typename Expression>
-					using _no_unknown_tables = detail::is_subset_of<typename Expression::_table_set, _known_tables>;
+						 return {{}, db.prepare_remove(_get_statement())};
+					 }
 			};
-	}
+	};
 
-	// REMOVE
-	template<typename Db,
-			typename... Policies
-				>
-		struct remove_t:
-			public detail::remove_policies_t<Db, Policies...>::_methods_t
+
+	template<typename Context>
+		struct serializer_t<Context, remove_name_t>
 		{
-			using _policies_t = typename detail::remove_policies_t<Db, Policies...>;
-			using _database_t = typename _policies_t::_database_t;
-			using _table_t = typename _policies_t::_table_t;
-			using _using_t = typename _policies_t::_using_t;
-			using _extra_tables_t = typename _policies_t::_extra_tables_t;
-			using _where_t = typename _policies_t::_where_t;
+			using T = remove_name_t;
 
-			using _is_dynamic = typename std::conditional<std::is_same<_database_t, void>::value, std::false_type, std::true_type>::type;
-
-			using _parameter_tuple_t = std::tuple<Policies...>;
-			using _parameter_list_t = typename make_parameter_list_t<remove_t>::type;
-
-			// Constructors
-			remove_t()
-			{}
-
-			template<typename Statement, typename T>
-				remove_t(Statement s, T t):
-					_table(detail::arg_selector<_table_t>::_(s._table, t)),
-					_using(detail::arg_selector<_using_t>::_(s._using, t)),
-					_where(detail::arg_selector<_where_t>::_(s._where, t))
-			{}
-
-			remove_t(const remove_t&) = default;
-			remove_t(remove_t&&) = default;
-			remove_t& operator=(const remove_t&) = default;
-			remove_t& operator=(remove_t&&) = default;
-			~remove_t() = default;
-
-			// run and prepare
-			static constexpr size_t _get_static_no_of_parameters()
+			static Context& _(const T& t, Context& context)
 			{
-				return _parameter_list_t::size::value;
+				context << "DELETE";
+
+				return context;
 			}
-
-			size_t _get_no_of_parameters() const
-			{
-				return _parameter_list_t::size::value;
-			}
-
-			template<typename A>
-				struct is_table_subset_of_table
-				{
-					static constexpr bool value = ::sqlpp::detail::is_subset_of<typename A::_table_set, typename _table_t::_table_set>::value;
-				};
-
-			void _check_consistency() const
-			{
-				static_assert(is_where_t<_where_t>::value, "cannot run update without having a where condition, use .where(true) to update all rows");
-
-				// FIXME: Read more details about what is allowed and what not in SQL DELETE
-				static_assert(is_table_subset_of_table<_where_t>::value, "where requires additional tables");
-			}
-
-			template<typename Database>
-				std::size_t _run(Database& db) const
-				{
-					_check_consistency();
-
-					static_assert(_get_static_no_of_parameters() == 0, "cannot run remove directly with parameters, use prepare instead");
-					return db.remove(*this);
-				}
-
-			template<typename Database>
-				auto _prepare(Database& db) const
-				-> prepared_remove_t<Database, remove_t>
-				{
-					_check_consistency();
-
-					return {{}, db.prepare_remove(*this)};
-				}
-
-			_table_t _table;
-			_using_t _using;
-			_where_t _where;
 		};
 
-	namespace vendor
-	{
-		template<typename Context, typename Database, typename... Policies>
-			struct serializer_t<Context, remove_t<Database, Policies...>>
-			{
-				using T = remove_t<Database, Policies...>;
+	template<typename Database>
+		using blank_remove_t = statement_t<Database,
+					remove_t,
+					no_from_t,
+					no_using_t,
+					no_extra_tables_t,
+					no_where_t<true>
+						>;
 
-				static Context& _(const T& t, Context& context)
-				{
-					context << "DELETE FROM ";
-					serialize(t._table, context);
-					serialize(t._using, context);
-					serialize(t._where, context);
-					return context;
-				}
-			};
-	}
-
-	template<typename Database, typename... Policies>
-		using make_remove_t = typename detail::remove_policies_t<Database, Policies...>::_statement_t;
+	auto remove()
+		-> blank_remove_t<void>
+		{
+			return { blank_remove_t<void>() };
+		}
 
 	template<typename Table>
-		constexpr auto remove_from(Table table)
-		-> make_remove_t<void, vendor::single_table_t<void, Table>>
+		auto remove_from(Table table)
+		-> decltype(blank_remove_t<void>().from(table))
 		{
-			return { make_remove_t<void>(), vendor::single_table_t<void, Table>{table} };
+			return { blank_remove_t<void>().from(table) };
+		}
+
+	template<typename Database>
+		auto  dynamic_remove(const Database&)
+		-> decltype(blank_remove_t<Database>())
+		{
+			return { blank_remove_t<Database>() };
 		}
 
 	template<typename Database, typename Table>
-		constexpr auto  dynamic_remove_from(const Database&, Table table)
-		-> make_remove_t<Database, vendor::single_table_t<void, Table>>
+		auto  dynamic_remove_from(const Database&, Table table)
+		-> decltype(blank_remove_t<Database>().from(table))
 		{
-			return { make_remove_t<Database>(), vendor::single_table_t<void, Table>{table} };
+			return { blank_remove_t<Database>().from(table) };
 		}
-
 }
 
 #endif

include/sqlpp11/result.h

@@ -45,12 +45,12 @@ namespace sqlpp
 			result_t() = default;
 
 			template<typename DynamicNames>
-			result_t(db_result_t&& result, const DynamicNames& dynamic_names):
-				_result(std::move(result)),
-				_result_row(dynamic_names)
-				{
-					_result.next(_result_row);
-				}
+				result_t(db_result_t&& result, const DynamicNames& dynamic_names):
+					_result(std::move(result)),
+					_result_row(dynamic_names)
+			{
+				_result.next(_result_row);
+			}
 
 			result_t(const result_t&) = delete;
 			result_t(result_t&&) = default;

include/sqlpp11/result_row.h

@@ -28,8 +28,7 @@
 #define SQLPP_RESULT_ROW_H
 
 #include <map>
-#include <sqlpp11/vendor/char_result_row.h>
-#include <sqlpp11/vendor/field.h>
+#include <sqlpp11/field.h>
 #include <sqlpp11/text.h>
 #include <sqlpp11/detail/column_index_sequence.h>
 
@@ -42,115 +41,86 @@ namespace sqlpp
 
 		template<typename Db, std::size_t index, typename NamedExpr>
 			struct result_field:
-				public NamedExpr::_name_t::template _member_t<typename NamedExpr::_value_type::template _result_entry_t<Db, NamedExpr::_trivial_value_is_null>>
+				public NamedExpr::_name_t::template _member_t<typename value_type_of<NamedExpr>::template _result_entry_t<Db, NamedExpr::_trivial_value_is_null>>
+		{
+			using _field = typename NamedExpr::_name_t::template _member_t<typename value_type_of<NamedExpr>::template _result_entry_t<Db, NamedExpr::_trivial_value_is_null>>;
+
+			result_field() = default;
+
+			void _validate()
 			{
-				using _field = typename NamedExpr::_name_t::template _member_t<typename NamedExpr::_value_type::template _result_entry_t<Db, NamedExpr::_trivial_value_is_null>>;
+				_field::operator()()._validate();
+			}
 
-				result_field() = default;
-				result_field(const char_result_row_t& char_result_row_t):
-					_field({{char_result_row_t.data[index], char_result_row_t.len[index]}})
-				{
-				}
+			void _invalidate()
+			{
+				_field::operator()()._invalidate();
+			}
 
-				result_field& operator=(const char_result_row_t& char_result_row_t)
-				{
-					_field::operator()().assign(char_result_row_t.data[index], char_result_row_t.len[index]);
-					return *this;
-				}
-
-				void validate()
-				{
-					_field::operator()().validate();
-				}
-
-				void invalidate()
-				{
-					_field::operator()().invalidate();
-				}
-
-				template<typename Target>
+			template<typename Target>
 				void _bind(Target& target)
 				{
 					_field::operator()()._bind(target, index);
 				}
-			};
+		};
 
 		template<std::size_t index, typename AliasProvider, typename Db, typename... NamedExprs>
-			struct result_field<Db, index, vendor::multi_field_t<AliasProvider, std::tuple<NamedExprs...>>>: 
-				public AliasProvider::_name_t::template _member_t<result_row_impl<Db, detail::make_column_index_sequence<index, NamedExprs...>, NamedExprs...>>
+			struct result_field<Db, index, multi_field_t<AliasProvider, std::tuple<NamedExprs...>>>: 
+			public AliasProvider::_name_t::template _member_t<result_row_impl<Db, detail::make_column_index_sequence<index, NamedExprs...>, NamedExprs...>>
 			{
 				using _multi_field = typename AliasProvider::_name_t::template _member_t<result_row_impl<Db, detail::make_column_index_sequence<index, NamedExprs...>, NamedExprs...>>;
 
 				result_field() = default;
-				result_field(const char_result_row_t& char_result_row_t):
-					_multi_field({char_result_row_t})
-				{}
 
-				result_field& operator=(const char_result_row_t& char_result_row_t)
+				void _validate()
 				{
-					_multi_field::operator()() = char_result_row_t;
-					return *this;
+					_multi_field::operator()()._validate();
 				}
 
-				void validate()
+				void _invalidate()
 				{
-					_multi_field::operator()().validate();
-				}
-
-				void invalidate()
-				{
-					_multi_field::operator()().invalidate();
+					_multi_field::operator()()._invalidate();
 				}
 
 				template<typename Target>
-				void _bind(Target& target)
-				{
-					_multi_field::operator()()._bind(target);
-				}
+					void _bind(Target& target)
+					{
+						_multi_field::operator()()._bind(target);
+					}
 			};
 
 		template<typename Db, std::size_t LastIndex, std::size_t... Is, typename... NamedExprs>
 			struct result_row_impl<Db, detail::column_index_sequence<LastIndex, Is...>, NamedExprs...>: 
-				public result_field<Db, Is, NamedExprs>...
+			public result_field<Db, Is, NamedExprs>...
 			{
 				static constexpr std::size_t _last_index = LastIndex;
+
 				result_row_impl() = default;
-				result_row_impl(const char_result_row_t& char_result_row):
-					result_field<Db, Is, NamedExprs>(char_result_row)...
-				{
-				}
 
-				result_row_impl& operator=(const char_result_row_t& char_result_row)
+				void _validate()
 				{
 					using swallow = int[];
-					(void) swallow{(result_field<Db, Is, NamedExprs>::operator=(char_result_row), 0)...};
-					return *this;
+					(void) swallow{(result_field<Db, Is, NamedExprs>::_validate(), 0)...};
 				}
 
-				void validate()
+				void _invalidate()
 				{
 					using swallow = int[];
-					(void) swallow{(result_field<Db, Is, NamedExprs>::validate(), 0)...};
-				}
-
-				void invalidate()
-				{
-					using swallow = int[];
-					(void) swallow{(result_field<Db, Is, NamedExprs>::invalidate(), 0)...};
+					(void) swallow{(result_field<Db, Is, NamedExprs>::_invalidate(), 0)...};
 				}
 
 				template<typename Target>
-				void _bind(Target& target)
-				{
-					using swallow = int[];
-					(void) swallow{(result_field<Db, Is, NamedExprs>::_bind(target), 0)...};
-				}
+					void _bind(Target& target)
+					{
+						using swallow = int[];
+						(void) swallow{(result_field<Db, Is, NamedExprs>::_bind(target), 0)...};
+					}
 			};
 
 	}
 
 	template<typename Db, typename... NamedExprs>
-	struct result_row_t: public detail::result_row_impl<Db, detail::make_column_index_sequence<0, NamedExprs...>, NamedExprs...>
+		struct result_row_t: public detail::result_row_impl<Db, detail::make_column_index_sequence<0, NamedExprs...>, NamedExprs...>
 	{
 		using _impl = detail::result_row_impl<Db, detail::make_column_index_sequence<0, NamedExprs...>, NamedExprs...>;
 		bool _is_valid;
@@ -163,9 +133,9 @@ namespace sqlpp
 		}
 
 		template<typename DynamicNames>
-		result_row_t(const DynamicNames&):
-			_impl(),
-			_is_valid(false)
+			result_row_t(const DynamicNames&):
+				_impl(),
+				_is_valid(false)
 		{
 		}
 
@@ -174,22 +144,15 @@ namespace sqlpp
 		result_row_t& operator=(const result_row_t&) = delete;
 		result_row_t& operator=(result_row_t&&) = default;
 
-		result_row_t& operator=(const char_result_row_t& char_result_row_t)
+		void _validate()
 		{
-			_impl::operator=(char_result_row_t);
-			_is_valid = true;
-			return *this;
-		}
-
-		void validate()
-		{
-			_impl::validate();
+			_impl::_validate();
 			_is_valid = true;
 		}
 
-		void invalidate()
+		void _invalidate()
 		{
-			_impl::invalidate();
+			_impl::_invalidate();
 			_is_valid = false;
 		}
 
@@ -209,14 +172,14 @@ namespace sqlpp
 		}
 
 		template<typename Target>
-			void bind_result(Target& target)
+			void _bind(Target& target)
 			{
 				_impl::_bind(target);
 			}
 	};
 
 	template<typename Db, typename... NamedExprs>
-	struct dynamic_result_row_t: public detail::result_row_impl<Db, detail::make_column_index_sequence<0, NamedExprs...>, NamedExprs...>
+		struct dynamic_result_row_t: public detail::result_row_impl<Db, detail::make_column_index_sequence<0, NamedExprs...>, NamedExprs...>
 	{
 		using _impl = detail::result_row_impl<Db, detail::make_column_index_sequence<0, NamedExprs...>, NamedExprs...>;
 		using _field_type = detail::text::_result_entry_t<Db, false>;
@@ -237,6 +200,10 @@ namespace sqlpp
 			_is_valid(false),
 			_dynamic_columns(dynamic_columns)
 		{
+			for (auto name : _dynamic_columns)
+			{
+				_dynamic_fields.insert({name, _field_type{}});
+			}
 		}
 
 		dynamic_result_row_t(const dynamic_result_row_t&) = delete;
@@ -244,31 +211,24 @@ namespace sqlpp
 		dynamic_result_row_t& operator=(const dynamic_result_row_t&) = delete;
 		dynamic_result_row_t& operator=(dynamic_result_row_t&&) = default;
 
-		dynamic_result_row_t& operator=(const char_result_row_t& char_result_row)
+		void _validate()
 		{
-			_impl::operator=(char_result_row);
+
+			_impl::_validate();
 			_is_valid = true;
-
-			char_result_row_t dynamic_row = char_result_row;
-
-			dynamic_row.data += _last_static_index;
-			dynamic_row.len += _last_static_index;
-			for (const auto& column : _dynamic_columns)
+			for (auto& field : _dynamic_fields)
 			{
-				_dynamic_fields[column].assign(dynamic_row.data[0], dynamic_row.len[0]);
-				++dynamic_row.data;
-				++dynamic_row.len;
+				field.second._validate();
 			}
-			return *this;
 		}
 
-		void invalidate()
+		void _invalidate()
 		{
-			_impl::invalidate();
+			_impl::_invalidate();
 			_is_valid = false;
 			for (auto& field : _dynamic_fields)
 			{
-				field.second.invalidate();
+				field.second._invalidate();
 			}
 		}
 
@@ -287,6 +247,17 @@ namespace sqlpp
 			return _is_valid;
 		}
 
+		template<typename Target>
+			void _bind(Target& target)
+			{
+				_impl::_bind(target);
+
+				std::size_t index = _last_static_index;
+				for (const auto& name  : _dynamic_columns)
+				{
+					_dynamic_fields.at(name)._bind(target, ++index);
+				}
+			}
 	};
 }
 

include/sqlpp11/select.h

@@ -27,332 +27,81 @@
 #ifndef SQLPP_SELECT_H
 #define SQLPP_SELECT_H
 
-#include <sqlpp11/result.h>
-#include <sqlpp11/parameter_list.h>
-#include <sqlpp11/prepared_select.h>
+#include <sqlpp11/statement.h>
 
-#include <sqlpp11/vendor/noop.h>
-#include <sqlpp11/vendor/select_flag_list.h>
-#include <sqlpp11/vendor/select_column_list.h>
-#include <sqlpp11/vendor/from.h>
-#include <sqlpp11/vendor/extra_tables.h>
-#include <sqlpp11/vendor/where.h>
-#include <sqlpp11/vendor/group_by.h>
-#include <sqlpp11/vendor/having.h>
-#include <sqlpp11/vendor/order_by.h>
-#include <sqlpp11/vendor/limit.h>
-#include <sqlpp11/vendor/offset.h>
-#include <sqlpp11/vendor/expression.h>
-#include <sqlpp11/vendor/serializer.h>
-#include <sqlpp11/vendor/wrong.h>
-#include <sqlpp11/vendor/policy_update.h>
+#include <sqlpp11/noop.h>
+#include <sqlpp11/select_flag_list.h>
+#include <sqlpp11/select_column_list.h>
+#include <sqlpp11/from.h>
+#include <sqlpp11/extra_tables.h>
+#include <sqlpp11/where.h>
+#include <sqlpp11/group_by.h>
+#include <sqlpp11/having.h>
+#include <sqlpp11/order_by.h>
+#include <sqlpp11/limit.h>
+#include <sqlpp11/offset.h>
+#include <sqlpp11/expression.h>
+#include <sqlpp11/wrong.h>
 
-#include <sqlpp11/detail/arg_selector.h>
 
 namespace sqlpp
 {
-	template<typename Db,
-			typename... Policies
-				>
-		struct select_t;
+	struct select_name_t {};
 
-	namespace detail
-	{
-		template<typename Db = void,
-			typename FlagList = vendor::no_select_flag_list_t, 
-			typename ColumnList = vendor::no_select_column_list_t, 
-			typename From = vendor::no_from_t,
-			typename ExtraTables = vendor::no_extra_tables_t,
-			typename Where = vendor::no_where_t, 
-			typename GroupBy = vendor::no_group_by_t, 
-			typename Having = vendor::no_having_t,
-			typename OrderBy = vendor::no_order_by_t, 
-			typename Limit = vendor::no_limit_t, 
-			typename Offset = vendor::no_offset_t
-				>
-			struct select_policies_t
-			{
-				using _database_t = Db;
-				using _flag_list_t = FlagList;
-				using _column_list_t = ColumnList;
-				using _from_t = From;
-				using _extra_tables_t = ExtraTables;
-				using _where_t = Where;
-				using _group_by_t = GroupBy;
-				using _having_t = Having;
-				using _order_by_t = OrderBy;
-				using _limit_t = Limit;
-				using _offset_t = Offset;
+	struct select_t: public statement_name_t<select_name_t>
+	{};
 
-				using _statement_t = select_t<Db, FlagList, ColumnList, From, ExtraTables, Where, GroupBy, Having, OrderBy, Limit, Offset>;
-
-				struct _methods_t:
-					public _flag_list_t::template _methods_t<select_policies_t>,
-					public _column_list_t::template _methods_t<select_policies_t>,
-					public _from_t::template _methods_t<select_policies_t>,
-					public _extra_tables_t::template _methods_t<select_policies_t>,
-					public _where_t::template _methods_t<select_policies_t>,
-					public _group_by_t::template _methods_t<select_policies_t>,
-					public _having_t::template _methods_t<select_policies_t>,
-					public _order_by_t::template _methods_t<select_policies_t>,
-					public _limit_t::template _methods_t<select_policies_t>,
-					public _offset_t::template _methods_t<select_policies_t>
-				{};
-
-				template<typename Needle, typename Replacement, typename... Policies>
-					struct _policies_update_t
-					{
-						static_assert(detail::is_element_of<Needle, make_type_set_t<Policies...>>::value, "policies update for non-policy class detected");
-						using type =  select_t<Db, vendor::policy_update_t<Policies, Needle, Replacement>...>;
-					};
-
-				template<typename Needle, typename Replacement>
-					using _new_statement_t = typename _policies_update_t<Needle, Replacement, FlagList, ColumnList, From, ExtraTables, Where, GroupBy, Having, OrderBy, Limit, Offset>::type;
-
-				static_assert(is_noop_t<ColumnList>::value or sqlpp::is_select_column_list_t<ColumnList>::value, "column list of select is neither naught nor a valid column list");
-				static_assert(is_noop_t<From>::value or sqlpp::is_from_t<From>::value, "from() part of select is neither naught nor a valid from()");
-
-				using _known_tables = detail::make_joined_set_t<typename _from_t::_table_set, typename _extra_tables_t::_table_set>;
-
-				template<typename Expression>
-					using _no_unknown_tables = detail::is_subset_of<typename Expression::_table_set, _known_tables>;
-
-				using _required_tables = 
-					detail::make_joined_set_t<
-						typename _flag_list_t::_table_set,
-						typename _column_list_t::_table_set,
-						typename _where_t::_table_set,
-						typename _group_by_t::_table_set,
-						typename _having_t::_table_set,
-						typename _order_by_t::_table_set,
-						typename _limit_t::_table_set,
-						typename _offset_t::_table_set
-							>;
-
-				// The tables not covered by the from.
-				using _table_set = detail::make_difference_set_t<
-					_required_tables,
-					typename _from_t::_table_set // Hint: extra_tables_t is not used here because it is just a helper for dynamic .add_*() methods and should not change the structural integrity
-							>;
-
-				// A select can be used as a pseudo table if
-				//   - at least one column is selected
-				//   - the select is complete (leaks no tables)
-				using _can_be_used_as_table = typename std::conditional<
-					is_select_column_list_t<_column_list_t>::value and _table_set::size::value == 0,
-					std::true_type,
-					std::false_type
-					>::type;
-
-				using _value_type = typename std::conditional<
-					is_select_column_list_t<_column_list_t>::value and is_subset_of<typename _column_list_t::_table_set, typename _from_t::_table_set>::value,
-					typename ColumnList::_value_type,
-					no_value_t // If something is selected that requires a table, then we require a from for this to be a value
-						>::type;
-			};
-	}
-
-	// SELECT
-	template<typename Db,
-			typename... Policies
-				>
-		struct select_t:
-			public detail::select_policies_t<Db, Policies...>::_value_type::template expression_operators<select_t<Db, Policies...>>,
-			public detail::select_policies_t<Db, Policies...>::_methods_t
+	template<typename Context>
+		struct serializer_t<Context, select_name_t>
 		{
-			using _policies_t = typename detail::select_policies_t<Db, Policies...>;
-			using _database_t = typename _policies_t::_database_t;
-			using _flag_list_t = typename _policies_t::_flag_list_t;
-			using _column_list_t = typename _policies_t::_column_list_t;
-			using _from_t = typename _policies_t::_from_t;
-			using _extra_tables_t = typename _policies_t::_extra_tables_t;
-			using _where_t = typename _policies_t::_where_t;
-			using _group_by_t = typename _policies_t::_group_by_t;
-			using _having_t = typename _policies_t::_having_t;
-			using _order_by_t = typename _policies_t::_order_by_t;
-			using _limit_t = typename _policies_t::_limit_t;
-			using _offset_t = typename _policies_t::_offset_t;
+			using T = select_name_t;
 
-			using _is_dynamic = typename std::conditional<std::is_same<_database_t, void>::value, std::false_type, std::true_type>::type;
-
-			using _parameter_tuple_t = std::tuple<Policies...>;
-			using _parameter_list_t = typename make_parameter_list_t<select_t>::type;
-			using _table_set = typename _policies_t::_table_set;
-			
-			template<typename Database>
-				using _result_row_t = typename _column_list_t::template _result_row_t<Database>;
-			using _dynamic_names_t = typename _column_list_t::_dynamic_names_t;
-
-			using _is_select = std::true_type;
-			using _requires_braces = std::true_type;
-
-			using _value_type = typename detail::select_policies_t<Db, Policies...>::_value_type;
-			using _name_t = typename _column_list_t::_name_t;
-
-			// Constructors
-			select_t()
-			{}
-
-			template<typename Statement, typename T>
-				select_t(Statement s, T t):
-					_flag_list(detail::arg_selector<_flag_list_t>::_(s._flag_list, t)),
-					_column_list(detail::arg_selector<_column_list_t>::_(s._column_list, t)),
-					_from(detail::arg_selector<_from_t>::_(s._from, t)),
-					_where(detail::arg_selector<_where_t>::_(s._where, t)),
-					_group_by(detail::arg_selector<_group_by_t>::_(s._group_by, t)),
-					_having(detail::arg_selector<_having_t>::_(s._having, t)),
-					_order_by(detail::arg_selector<_order_by_t>::_(s._order_by, t)),
-					_limit(detail::arg_selector<_limit_t>::_(s._limit, t)),
-					_offset(detail::arg_selector<_offset_t>::_(s._offset, t))
-			{}
-
-			select_t(const select_t& r) = default;
-			select_t(select_t&& r) = default;
-			select_t& operator=(const select_t& r) = default;
-			select_t& operator=(select_t&& r) = default;
-			~select_t() = default;
-
-			// PseudoTable
-			template<typename AliasProvider>
-				struct _pseudo_table_t
-				{
-					using table = typename _column_list_t::template _pseudo_table_t<select_t>;
-					using alias = typename table::template _alias_t<AliasProvider>;
-				};
-
-			template<typename AliasProvider>
-				typename _pseudo_table_t<AliasProvider>::alias as(const AliasProvider& aliasProvider) const
-				{
-					static_assert(_policies_t::_can_be_used_as_table::value, "select cannot be used as table, incomplete from()");
-					return typename _pseudo_table_t<AliasProvider>::table(
-							*this).as(aliasProvider);
-				}
-
-			const _dynamic_names_t& get_dynamic_names() const
+			static Context& _(const T& t, Context& context)
 			{
-				return _column_list._dynamic_columns._dynamic_expression_names;
+				context << "SELECT ";
+
+				return context;
 			}
-
-			static constexpr size_t _get_static_no_of_parameters()
-			{
-				return _parameter_list_t::size::value;
-			}
-
-			size_t _get_no_of_parameters() const
-			{
-				return _parameter_list_t::size::value;
-			}
-
-			size_t get_no_of_result_columns() const
-			{
-				return _column_list_t::static_size() + get_dynamic_names().size();
-			}
-
-			template<typename A>
-				struct is_table_subset_of_from
-				{
-					static constexpr bool value = ::sqlpp::detail::is_subset_of<typename A::_table_set, typename _from_t::_table_set>::value;
-				};
-
-			void _check_consistency() const
-			{
-				static_assert(is_select_column_list_t<_column_list_t>::value, "no columns selected");
-
-				static_assert(is_table_subset_of_from<_flag_list_t>::value, "flags require additional tables in from()");
-				static_assert(is_table_subset_of_from<_column_list_t>::value, "selected columns require additional tables in from()");
-				static_assert(is_table_subset_of_from<_where_t>::value, "where() expression requires additional tables in from()");
-				static_assert(is_table_subset_of_from<_group_by_t>::value, "group_by() expression requires additional tables in from()");
-				static_assert(is_table_subset_of_from<_having_t>::value, "having() expression requires additional tables in from()");
-				static_assert(is_table_subset_of_from<_order_by_t>::value, "order_by() expression requires additional tables in from()");
-				static_assert(is_table_subset_of_from<_limit_t>::value, "limit() expression requires additional tables in from()");
-				static_assert(is_table_subset_of_from<_offset_t>::value, "offset() expression requires additional tables in from()");
-				static_assert(not _table_set::size::value, "one sub expression contains tables which are not in the from()");
-			}
-
-			// Execute
-			template<typename Database>
-				auto _run(Database& db) const
-				-> result_t<decltype(db.select(*this)), _result_row_t<Database>>
-				{
-					_check_consistency();
-					static_assert(_get_static_no_of_parameters() == 0, "cannot run select directly with parameters, use prepare instead");
-
-					return {db.select(*this), get_dynamic_names()};
-				}
-
-			// Prepare
-			template<typename Database>
-				auto _prepare(Database& db) const
-				-> prepared_select_t<Database, select_t>
-				{
-					_check_consistency();
-
-					return {{}, get_dynamic_names(), db.prepare_select(*this)};
-				}
-
-			_flag_list_t _flag_list;
-			_column_list_t _column_list;
-			_from_t _from;
-			_where_t _where;
-			_group_by_t _group_by;
-			_having_t _having;
-			_order_by_t _order_by;
-			_limit_t _limit;
-			_offset_t _offset;
 		};
 
-	namespace vendor
-	{
-		template<typename Context, typename Database, typename... Policies>
-			struct serializer_t<Context, select_t<Database, Policies...>>
-			{
-				using T = select_t<Database, Policies...>;
+	template<typename Database>
+		using blank_select_t = statement_t<Database,
+					select_t,
+					no_select_flag_list_t, 
+					no_select_column_list_t, 
+					no_from_t,
+					no_extra_tables_t,
+					no_where_t<true>, 
+					no_group_by_t, 
+					no_having_t,
+					no_order_by_t, 
+					no_limit_t, 
+					no_offset_t>;
 
-				static Context& _(const T& t, Context& context)
-				{
-					context << "SELECT ";
 
-					serialize(t._flag_list, context);
-					serialize(t._column_list, context);
-					serialize(t._from, context);
-					serialize(t._where, context);
-					serialize(t._group_by, context);
-					serialize(t._having, context);
-					serialize(t._order_by, context);
-					serialize(t._limit, context);
-					serialize(t._offset, context);
-
-					return context;
-				}
-			};
-	}
-
-	template<typename Database, typename... Policies>
-		using make_select_t = typename detail::select_policies_t<Database, Policies...>::_statement_t;
-
-	make_select_t<void> select() // FIXME: These should be constexpr
+	blank_select_t<void> select() // FIXME: These should be constexpr
 	{
 		return { };
 	}
 
 	template<typename... Columns>
 		auto select(Columns... columns)
-		-> make_select_t<void, vendor::no_select_flag_list_t, detail::make_select_column_list_t<void, Columns...>>
+		-> decltype(blank_select_t<void>().columns(columns...))
 		{
-			return { make_select_t<void>(), detail::make_select_column_list_t<void, Columns...>{std::tuple_cat(detail::as_tuple<Columns>::_(columns)...)} };
+			return blank_select_t<void>().columns(columns...);
 		}
 
 	template<typename Database>
-		make_select_t<Database> dynamic_select(const Database&)
+		blank_select_t<Database> dynamic_select(const Database&)
 		{
-			return { make_select_t<Database>() };
+			return { };
 		}
 
 	template<typename Database, typename... Columns>
 		auto dynamic_select(const Database&, Columns... columns)
-		-> make_select_t<Database, vendor::no_select_flag_list_t, detail::make_select_column_list_t<void, Columns...>>
+		-> decltype(blank_select_t<Database>().columns(columns...))
 		{
-			return { make_select_t<Database>(), detail::make_select_column_list_t<void, Columns...>(std::tuple_cat(detail::as_tuple<Columns>::_(columns)...)) };
+			return blank_select_t<Database>().columns(columns...);
 		}
 
 }

include/sqlpp11/select_column_list.h

@@ -0,0 +1,397 @@
+/*
+ * Copyright (c) 2013-2014, Roland Bock
+ * All rights reserved.
+ * 
+ * Redistribution and use in source and binary forms, with or without modification,
+ * are permitted provided that the following conditions are met:
+ * 
+ *   Redistributions of source code must retain the above copyright notice, this
+ *   list of conditions and the following disclaimer.
+ * 
+ *   Redistributions in binary form must reproduce the above copyright notice, this
+ *   list of conditions and the following disclaimer in the documentation and/or
+ *   other materials provided with the distribution.
+ * 
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR
+ * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+ * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef SQLPP_SELECT_COLUMN_LIST_H
+#define SQLPP_SELECT_COLUMN_LIST_H
+
+#include <tuple>
+#include <sqlpp11/result_row.h>
+#include <sqlpp11/table.h>
+#include <sqlpp11/no_value.h>
+#include <sqlpp11/field.h>
+#include <sqlpp11/expression_fwd.h>
+#include <sqlpp11/select_pseudo_table.h>
+#include <sqlpp11/named_interpretable.h>
+#include <sqlpp11/interpret_tuple.h>
+#include <sqlpp11/policy_update.h>
+#include <sqlpp11/detail/type_set.h>
+#include <sqlpp11/detail/copy_tuple_args.h>
+
+namespace sqlpp
+{
+	namespace detail
+	{
+		template<typename... Columns>
+			struct select_traits
+			{
+				using _traits = make_traits<no_value_t, tag::select_column_list, tag::return_value>;
+				struct _name_t {};
+			};
+
+		template<typename Column>
+			struct select_traits<Column>
+			{
+				using _traits = make_traits<value_type_of<Column>, tag::select_column_list, tag::return_value, tag::expression, tag::named_expression>;
+				using _name_t = typename Column::_name_t;
+			};
+	}
+
+	template<typename Db>
+		struct dynamic_select_column_list
+		{
+			using _names_t = std::vector<std::string>;
+			std::vector<named_interpretable_t<Db>> _dynamic_columns;
+			_names_t _dynamic_expression_names;
+
+			template<typename Expr>
+				void emplace_back(Expr expr)
+				{
+					_dynamic_expression_names.push_back(Expr::_name_t::_get_name());
+					_dynamic_columns.emplace_back(expr);
+				}
+
+			bool empty() const
+			{
+				return _dynamic_columns.empty();
+			}
+		};
+
+	template<>
+		struct dynamic_select_column_list<void>
+		{
+			struct _names_t
+			{
+				static constexpr size_t size() { return 0; }
+			};
+			_names_t _dynamic_expression_names;
+
+			static constexpr bool empty()
+			{
+				return true;
+			}
+		};
+
+	template<typename Context, typename Db>
+		struct serializer_t<Context, dynamic_select_column_list<Db>>
+		{
+			using T = dynamic_select_column_list<Db>;
+
+			static Context& _(const T& t, Context& context)
+			{
+				bool first = true;
+				for (const auto column : t._dynamic_columns)
+				{
+					if (first)
+						first = false;
+					else
+						context << ',';
+					serialize(column, context);
+				}
+				return context;
+			}
+		};
+
+	template<typename Context>
+		struct serializer_t<Context, dynamic_select_column_list<void>>
+		{
+			using T = dynamic_select_column_list<void>;
+
+			static Context& _(const T& t, Context& context)
+			{
+				return context;
+			}
+		};
+
+	// SELECTED COLUMNS DATA
+	template<typename Database, typename... Columns>
+		struct select_column_list_data_t
+		{
+			select_column_list_data_t(Columns... columns):
+				_columns(columns...)
+			{}
+
+			select_column_list_data_t(std::tuple<Columns...> columns):
+				_columns(columns)
+			{}
+
+			select_column_list_data_t(const select_column_list_data_t&) = default;
+			select_column_list_data_t(select_column_list_data_t&&) = default;
+			select_column_list_data_t& operator=(const select_column_list_data_t&) = default;
+			select_column_list_data_t& operator=(select_column_list_data_t&&) = default;
+			~select_column_list_data_t() = default;
+
+			std::tuple<Columns...> _columns;
+			dynamic_select_column_list<Database> _dynamic_columns;
+		};
+
+
+	// SELECTED COLUMNS
+	template<typename Database, typename... Columns>
+		struct select_column_list_t
+		{
+			using _traits = typename ::sqlpp::detail::select_traits<Columns...>::_traits;
+			using _recursive_traits = make_recursive_traits<Columns...>;
+
+			using _name_t = typename ::sqlpp::detail::select_traits<Columns...>::_name_t;
+
+			using _is_dynamic = is_database<Database>;
+
+			static_assert(_is_dynamic::value or sizeof...(Columns), "at least one select expression required");
+			static_assert(not ::sqlpp::detail::has_duplicates<Columns...>::value, "at least one duplicate argument detected");
+			static_assert(::sqlpp::detail::all_t<(is_named_expression_t<Columns>::value or is_multi_column_t<Columns>::value)...>::value, "at least one argument is not a named expression");
+			static_assert(not ::sqlpp::detail::has_duplicates<typename Columns::_name_t...>::value, "at least one duplicate name detected");
+
+			struct _column_type {};
+
+			// Data
+			using _data_t = select_column_list_data_t<Database, Columns...>;
+
+			// Member implementation with data and methods
+			template<typename Policies>
+				struct _impl_t
+				{
+					template<typename NamedExpression>
+						void add_ntc(NamedExpression namedExpression)
+						{
+							add<NamedExpression, std::false_type>(namedExpression);
+						}
+
+					template<typename NamedExpression, typename TableCheckRequired = std::true_type>
+						void add(NamedExpression namedExpression)
+						{
+							static_assert(_is_dynamic::value, "selected_columns::add() can only be called for dynamic_column");
+							static_assert(is_named_expression_t<NamedExpression>::value, "invalid named expression argument in selected_columns::add()");
+							static_assert(TableCheckRequired::value or Policies::template _no_unknown_tables<NamedExpression>::value, "named expression uses tables unknown to this statement in selected_columns::add()");
+							using column_names = ::sqlpp::detail::make_type_set_t<typename Columns::_name_t...>;
+							static_assert(not ::sqlpp::detail::is_element_of<typename NamedExpression::_name_t, column_names>::value, "a column of this name is present in the select already");
+
+							using ok = ::sqlpp::detail::all_t<
+								_is_dynamic::value, 
+								is_named_expression_t<NamedExpression>::value
+									>;
+
+							_add_impl(namedExpression, ok()); // dispatch to prevent compile messages after the static_assert
+						}
+
+					//private:
+					template<typename NamedExpression>
+						void _add_impl(NamedExpression namedExpression, const std::true_type&)
+						{
+							return _data._dynamic_columns.emplace_back(namedExpression);
+						}
+
+					template<typename NamedExpression>
+						void _add_column_impl(NamedExpression namedExpression, const std::false_type&);
+
+				public:
+					_data_t _data;
+				};
+
+			// Member template for adding the named member to a statement
+			template<typename Policies>
+				struct _member_t
+				{
+					using _data_t = select_column_list_data_t<Database, Columns...>;
+
+					_impl_t<Policies> selected_columns;
+					_impl_t<Policies>& operator()() { return selected_columns; }
+					const _impl_t<Policies>& operator()() const { return selected_columns; }
+
+					template<typename T>
+						static auto _get_member(T t) -> decltype(t.selected_columns)
+						{
+							return t.selected_columns;
+						}
+				};
+
+			// Additional methods for the statement
+			template<typename Policies>
+				struct _methods_t
+				{
+					static void _check_consistency() {}
+				};
+
+			// Result methods
+			template<typename Policies>
+				struct _result_methods_t
+				{
+					using _statement_t = typename Policies::_statement_t;
+
+					const _statement_t& _get_statement() const
+					{
+						return static_cast<const _statement_t&>(*this);
+					}
+
+					template<typename Db>
+						using _result_row_t = typename std::conditional<_is_dynamic::value,
+									dynamic_result_row_t<Db, make_field_t<Columns>...>,
+									result_row_t<Db, make_field_t<Columns>...>>::type;
+
+					using _dynamic_names_t = typename dynamic_select_column_list<Database>::_names_t;
+
+					template<typename AliasProvider>
+						struct _deferred_table_t
+						{
+							using table = select_pseudo_table_t<_statement_t, Columns...>;
+							using alias = typename table::template _alias_t<AliasProvider>;
+						};
+
+					template<typename AliasProvider>
+						using _table_t = typename _deferred_table_t<AliasProvider>::table;
+
+					template<typename AliasProvider>
+						using _alias_t = typename _deferred_table_t<AliasProvider>::alias;
+
+					template<typename AliasProvider>
+						_alias_t<AliasProvider> as(const AliasProvider& aliasProvider) const
+						{
+							static_assert(Policies::_can_be_used_as_table::value, "statement cannot be used as table, e.g. due to missing tables");
+							static_assert(::sqlpp::detail::none_t<is_multi_column_t<Columns>::value...>::value, "cannot use multi-columns in sub selects");
+							return _table_t<AliasProvider>(_get_statement()).as(aliasProvider);
+						}
+
+					const _dynamic_names_t& get_dynamic_names() const
+					{
+						return _get_statement().selected_columns._data._dynamic_columns._dynamic_expression_names;
+					}
+
+					size_t get_no_of_result_columns() const
+					{
+						return sizeof...(Columns) + get_dynamic_names().size();
+					}
+
+					// Execute
+					template<typename Db>
+						auto _run(Db& db) const
+						-> result_t<decltype(db.select(this->_get_statement())), _result_row_t<Db>>
+						{
+							_statement_t::_check_consistency();
+							static_assert(_statement_t::_get_static_no_of_parameters() == 0, "cannot run select directly with parameters, use prepare instead");
+
+							return {db.select(_get_statement()), get_dynamic_names()};
+						}
+
+					// Prepare
+					template<typename Db>
+						auto _prepare(Db& db) const
+						-> prepared_select_t<Db, _statement_t>
+						{
+							_statement_t::_check_consistency();
+
+							return {{}, get_dynamic_names(), db.prepare_select(_get_statement())};
+						}
+				};
+
+		};
+
+	namespace detail
+	{
+		template<typename Database, typename... Columns>
+			using make_select_column_list_t = 
+			copy_tuple_args_t<select_column_list_t, Database, 
+			decltype(std::tuple_cat(as_tuple<Columns>::_(std::declval<Columns>())...))>;
+	}
+
+	struct no_select_column_list_t
+	{
+		using _traits = make_traits<no_value_t, ::sqlpp::tag::noop, ::sqlpp::tag::missing>;
+		using _recursive_traits = make_recursive_traits<>;
+
+		struct _name_t {};
+
+		// Data
+		using _data_t = no_data_t;
+
+		// Member implementation with data and methods
+		template<typename Policies>
+			struct _impl_t
+			{
+				_data_t _data;
+			};
+
+		// Member template for adding the named member to a statement
+		template<typename Policies>
+			struct _member_t
+			{
+				using _data_t = no_data_t;
+
+				_impl_t<Policies> no_selected_columns;
+				_impl_t<Policies>& operator()() { return no_selected_columns; }
+				const _impl_t<Policies>& operator()() const { return no_selected_columns; }
+
+				template<typename T>
+					static auto _get_member(T t) -> decltype(t.no_selected_columns)
+					{
+						return t.no_selected_columns;
+					}
+			};
+
+		// Additional methods for the statement
+		template<typename Policies>
+			struct _methods_t
+			{
+				using _database_t = typename Policies::_database_t;
+				template<typename T>
+					using _new_statement_t = typename Policies::template _new_statement_t<no_select_column_list_t, T>;
+
+				static void _check_consistency() {}
+
+				template<typename... Args>
+					auto columns(Args... args)
+					-> _new_statement_t<::sqlpp::detail::make_select_column_list_t<void, Args...>>
+					{
+						return { *static_cast<typename Policies::_statement_t*>(this), typename ::sqlpp::detail::make_select_column_list_t<void, Args...>::_data_t{std::tuple_cat(::sqlpp::detail::as_tuple<Args>::_(args)...)} };
+					}
+
+				template<typename... Args>
+					auto dynamic_columns(Args... args)
+					-> _new_statement_t<::sqlpp::detail::make_select_column_list_t<_database_t, Args...>>
+					{
+						static_assert(not std::is_same<_database_t, void>::value, "dynamic_columns must not be called in a static statement");
+						return { *static_cast<typename Policies::_statement_t*>(this), typename ::sqlpp::detail::make_select_column_list_t<_database_t, Args...>::_data_t{std::tuple_cat(::sqlpp::detail::as_tuple<Args>::_(args)...)} };
+					}
+			};
+	};
+
+	// Interpreters
+	template<typename Context, typename Database, typename... Columns>
+		struct serializer_t<Context, select_column_list_data_t<Database, Columns...>>
+		{
+			using T = select_column_list_data_t<Database, Columns...>;
+
+			static Context& _(const T& t, Context& context)
+			{
+				interpret_tuple(t._columns, ',', context);
+				if (sizeof...(Columns) and not t._dynamic_columns.empty())
+					context << ',';
+				serialize(t._dynamic_columns, context);
+				return context;
+			}
+		};
+
+}
+
+#endif

include/sqlpp11/select_flag_list.h

@@ -0,0 +1,215 @@
+/*
+ * Copyright (c) 2013-2014, Roland Bock
+ * All rights reserved.
+ * 
+ * Redistribution and use in source and binary forms, with or without modification,
+ * are permitted provided that the following conditions are met:
+ * 
+ *   Redistributions of source code must retain the above copyright notice, this
+ *   list of conditions and the following disclaimer.
+ * 
+ *   Redistributions in binary form must reproduce the above copyright notice, this
+ *   list of conditions and the following disclaimer in the documentation and/or
+ *   other materials provided with the distribution.
+ * 
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR
+ * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+ * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef SQLPP_SELECT_FLAG_LIST_H
+#define SQLPP_SELECT_FLAG_LIST_H
+
+#include <tuple>
+#include <sqlpp11/type_traits.h>
+#include <sqlpp11/no_data.h>
+#include <sqlpp11/select_flags.h>
+#include <sqlpp11/detail/type_set.h>
+#include <sqlpp11/interpret_tuple.h>
+#include <sqlpp11/policy_update.h>
+
+namespace sqlpp
+{
+	// SELECTED FLAGS DATA
+	template<typename Database, typename... Flags>
+		struct select_flag_list_data_t
+		{
+			select_flag_list_data_t(Flags... flags):
+				_flags(flags...)
+			{}
+
+			select_flag_list_data_t(const select_flag_list_data_t&) = default;
+			select_flag_list_data_t(select_flag_list_data_t&&) = default;
+			select_flag_list_data_t& operator=(const select_flag_list_data_t&) = default;
+			select_flag_list_data_t& operator=(select_flag_list_data_t&&) = default;
+			~select_flag_list_data_t() = default;
+
+			std::tuple<Flags...> _flags;
+			interpretable_list_t<Database> _dynamic_flags;
+		};
+
+	// SELECT FLAGS
+	template<typename Database, typename... Flags>
+		struct select_flag_list_t
+		{
+			using _traits = make_traits<no_value_t, ::sqlpp::tag::select_flag_list>;
+			using _recursive_traits = make_recursive_traits<Flags...>;
+
+			using _is_dynamic = is_database<Database>;
+
+			static_assert(not ::sqlpp::detail::has_duplicates<Flags...>::value, "at least one duplicate argument detected in select flag list");
+
+			static_assert(::sqlpp::detail::all_t<is_select_flag_t<Flags>::value...>::value, "at least one argument is not a select flag in select flag list");
+
+			// Data
+			using _data_t = select_flag_list_data_t<Database, Flags...>;
+
+			// Member implementation with data and methods
+			template<typename Policies>
+				struct _impl_t
+				{
+					template<typename Flag>
+						void add_ntc(Flag flag)
+						{
+							add<Flag, std::false_type>(flag);
+						}
+
+					template<typename Flag, typename TableCheckRequired = std::true_type>
+						void add(Flag flag)
+						{
+							static_assert(_is_dynamic::value, "select_flags::add() must not be called for static select flags");
+							static_assert(is_select_flag_t<Flag>::value, "invalid select flag argument in select_flags::add()");
+							static_assert(TableCheckRequired::value or Policies::template _no_unknown_tables<Flag>::value, "flag uses tables unknown to this statement in select_flags::add()");
+
+							using ok = ::sqlpp::detail::all_t<_is_dynamic::value, is_select_flag_t<Flag>::value>;
+
+							_add_impl(flag, ok()); // dispatch to prevent compile messages after the static_assert
+						}
+
+				private:
+					template<typename Flag>
+						void _add_impl(Flag flag, const std::true_type&)
+						{
+							return _data._dynamic_flags.emplace_back(flag);
+						}
+
+					template<typename Flag>
+						void _add_impl(Flag flag, const std::false_type&);
+				public:
+					_data_t _data;
+				};
+
+			// Member template for adding the named member to a statement
+			template<typename Policies>
+				struct _member_t
+				{
+					using _data_t = select_flag_list_data_t<Database, Flags...>;
+
+					_impl_t<Policies> select_flags;
+					_impl_t<Policies>& operator()() { return select_flags; }
+					const _impl_t<Policies>& operator()() const { return select_flags; }
+
+					template<typename T>
+						static auto _get_member(T t) -> decltype(t.select_flags)
+						{
+							return t.select_flags;
+						}
+				};
+
+			// Additional methods for the statement
+			template<typename Policies>
+				struct _methods_t
+				{
+					static void _check_consistency() {}
+				};
+
+		};
+
+	struct no_select_flag_list_t
+	{
+		using _traits = make_traits<no_value_t, ::sqlpp::tag::noop>;
+		using _recursive_traits = make_recursive_traits<>;
+
+		// Data
+		using _data_t = no_data_t;
+
+		// Member implementation with data and methods
+		template<typename Policies>
+			struct _impl_t
+			{
+				_data_t _data;
+			};
+
+		// Member template for adding the named member to a statement
+		template<typename Policies>
+			struct _member_t
+			{
+				using _data_t = no_data_t;
+
+				_impl_t<Policies> no_select_flags;
+				_impl_t<Policies>& operator()() { return no_select_flags; }
+				const _impl_t<Policies>& operator()() const { return no_select_flags; }
+
+				template<typename T>
+					static auto _get_member(T t) -> decltype(t.no_select_flags)
+					{
+						return t.no_select_flags;
+					}
+			};
+
+		template<typename Policies>
+			struct _methods_t
+			{
+				using _database_t = typename Policies::_database_t;
+				template<typename T>
+					using _new_statement_t = typename Policies::template _new_statement_t<no_select_flag_list_t, T>;
+
+				static void _check_consistency() {}
+
+				template<typename... Args>
+					auto flags(Args... args)
+					-> _new_statement_t<select_flag_list_t<void, Args...>>
+					{
+						return { *static_cast<typename Policies::_statement_t*>(this), select_flag_list_data_t<void, Args...>{args...} };
+					}
+
+				template<typename... Args>
+					auto dynamic_flags(Args... args)
+					-> _new_statement_t<select_flag_list_t<_database_t, Args...>>
+					{
+						static_assert(not std::is_same<_database_t, void>::value, "dynamic_flags must not be called in a static statement");
+						return { *static_cast<typename Policies::_statement_t*>(this), select_flag_list_data_t<_database_t, Args...>{args...} };
+					}
+			};
+	};
+
+
+	// Interpreters
+	template<typename Context, typename Database, typename... Flags>
+		struct serializer_t<Context, select_flag_list_data_t<Database, Flags...>>
+		{
+			using T = select_flag_list_data_t<Database, Flags...>;
+
+			static Context& _(const T& t, Context& context)
+			{
+				interpret_tuple(t._flags, ' ', context);
+				if (sizeof...(Flags))
+					context << ' ';
+				interpret_list(t._dynamic_flags, ',', context);
+				if (not t._dynamic_flags.empty())
+					context << ' ';
+				return context;
+			}
+		};
+
+
+}
+
+#endif

include/sqlpp11/select_flags.h

@@ -29,7 +29,7 @@
 
 #include <sqlpp11/type_traits.h>
 #include <sqlpp11/detail/type_set.h>
-#include <sqlpp11/vendor/interpret_tuple.h>
+#include <sqlpp11/interpret_tuple.h>
 #include <tuple>
 
 namespace sqlpp
@@ -37,72 +37,54 @@ namespace sqlpp
 	// standard select flags
 	struct all_t
 	{
-		struct _value_type 
-		{ 
-			using _is_select_flag = std::true_type; 
-		};
-		using _table_set = detail::type_set<>;
+		using _traits = make_traits<no_value_t, tag::select_flag>;
+		using _recursive_traits = make_recursive_traits<>;
 	};
 	static constexpr all_t all = {};
 
-	namespace vendor
-	{
-		template<typename Context>
-			struct serializer_t<Context, all_t>
+	template<typename Context>
+		struct serializer_t<Context, all_t>
+		{
+			static Context& _(const all_t&, Context& context)
 			{
-				static Context& _(const all_t&, Context& context)
-				{
-					context << "ALL";
-					return context;
-				}
-			};
-	}
+				context << "ALL";
+				return context;
+			}
+		};
 
 	struct distinct_t
 	{
-		struct _value_type 
-		{ 
-			using _is_select_flag = std::true_type; 
-		};
-		using _table_set = detail::type_set<>;
+		using _traits = make_traits<no_value_t, tag::select_flag>;
+		using _recursive_traits = make_recursive_traits<>;
 	};
 	static constexpr distinct_t distinct = {};
 
-	namespace vendor
-	{
-		template<typename Context>
-			struct serializer_t<Context, distinct_t>
+	template<typename Context>
+		struct serializer_t<Context, distinct_t>
+		{
+			static Context& _(const distinct_t&, Context& context)
 			{
-				static Context& _(const distinct_t&, Context& context)
-				{
-					context << "DISTINCT";
-					return context;
-				}
-			};
-	}
+				context << "DISTINCT";
+				return context;
+			}
+		};
 
 	struct straight_join_t
 	{
-		struct _value_type 
-		{ 
-			using _is_select_flag = std::true_type; 
-		};
-		using _table_set = detail::type_set<>;
+		using _traits = make_traits<no_value_t, tag::select_flag>;
+		using _recursive_traits = make_recursive_traits<>;
 	};
 	static constexpr straight_join_t straight_join = {};
 
-	namespace vendor
-	{
-		template<typename Context>
-			struct serializer_t<Context, straight_join_t>
+	template<typename Context>
+		struct serializer_t<Context, straight_join_t>
+		{
+			static Context& _(const straight_join_t&, Context& context)
 			{
-				static Context& _(const straight_join_t&, Context& context)
-				{
-					context << "STRAIGHT_JOIN";
-					return context;
-				}
-			};
-	}
+				context << "STRAIGHT_JOIN";
+				return context;
+			}
+		};
 
 }
 

include/sqlpp11/select_pseudo_table.h

@@ -32,28 +32,31 @@
 namespace sqlpp
 {
 	// provide type information for sub-selects that are used as named expressions or tables
-	template<typename Expr>
+	template<typename ValueType, typename NameType>
 		struct select_column_spec_t
 		{
-			using _name_t = typename Expr::_name_t;
-			using _value_type = typename Expr::_value_type;
+			using _traits = make_traits<ValueType>;
+			using _recursive_traits = make_recursive_traits<>;
+			using _value_type = ValueType; // FIXME: column specs probably should use _traits, too
+
+			using _name_t = NameType;
 			struct _column_type 
 			{
-        using _must_not_insert = std::true_type;
-        using _must_not_update = std::true_type;
+				using _must_not_insert = std::true_type;
+				using _must_not_update = std::true_type;
 			};
 		};
 
 	template<
-						 typename Select,
+		typename Select,
 						 typename... NamedExpr
 							 >
 							 struct select_pseudo_table_t: public sqlpp::table_t<select_pseudo_table_t<
 																						 Select,
-																						 NamedExpr...>, select_column_spec_t<NamedExpr>...>
+																						 NamedExpr...>, select_column_spec_t<value_type_of<NamedExpr>, typename NamedExpr::_name_t>...>
 	{
-		using _value_type = no_value_t;
-		using _is_pseudo_table = std::true_type;
+		using _traits = make_traits<no_value_t, tag::table, tag::pseudo_table>;
+		using _recursive_traits = make_recursive_traits<>;
 
 		select_pseudo_table_t(Select select):
 			_select(select)
@@ -69,21 +72,18 @@ namespace sqlpp
 		Select _select;
 	};
 
-	namespace vendor
-	{
-		template<typename Context, typename Select, typename... NamedExpr>
-			struct serializer_t<Context, select_pseudo_table_t<Select, NamedExpr...>>
+	template<typename Context, typename Select, typename... NamedExpr>
+		struct serializer_t<Context, select_pseudo_table_t<Select, NamedExpr...>>
+		{
+			using T = select_pseudo_table_t<Select, NamedExpr...>;
+
+			static Context& _(const T& t, Context& context)
 			{
-				using T = select_pseudo_table_t<Select, NamedExpr...>;
+				serialize(t._select, context);
+				return context;
+			}
+		};
 
-				static Context& _(const T& t, Context& context)
-				{
-					serialize(t._select, context);
-					return context;
-				}
-			};
-
-	}
 }
 
 #endif

include/sqlpp11/serialize.h

@@ -27,28 +27,25 @@
 #ifndef SQLPP_SERIALIZE_H
 #define SQLPP_SERIALIZE_H
 
-#include <sqlpp11/vendor/serializer.h>
+#include <sqlpp11/serializer.h>
 
 namespace sqlpp
 {
 	template<typename T, typename Context>
 		auto serialize(const T& t, Context& context)
-		-> decltype(vendor::serializer_t<Context, T>::_(t, context))
+		-> decltype(serializer_t<Context, T>::_(t, context))
 		{
-			return vendor::serializer_t<Context, T>::_(t, context);
+			return serializer_t<Context, T>::_(t, context);
 		}
 
 	/*
-	namespace vendor // Required if you want to call serialize(sqlpp::value(7), printer), for instance
-	{
-		template<typename T, typename Context>
-			auto serialize(const T& t, Context& context)
-			-> decltype(vendor::serializer_t<Context, T>::_(t, context))
-			{
-				return vendor::serializer_t<Context, T>::_(t, context);
-			}
-	}
-	*/
+		 template<typename T, typename Context>
+		 auto serialize(const T& t, Context& context)
+		 -> decltype(serializer_t<Context, T>::_(t, context))
+		 {
+		 return serializer_t<Context, T>::_(t, context);
+		 }
+		 */
 
 }
 

include/sqlpp11/serializer.h

@@ -24,24 +24,21 @@
  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
-#ifndef SQLPP_VENDOR_SERIALIZER_H
-#define SQLPP_VENDOR_SERIALIZER_H
+#ifndef SQLPP_SERIALIZER_H
+#define SQLPP_SERIALIZER_H
 
-#include <sqlpp11/vendor/wrong.h>
+#include <sqlpp11/wrong.h>
 
 namespace sqlpp
 {
-	namespace vendor
-	{
-		template<typename Context, typename T, typename Enable = void>
-			struct serializer_t
+	template<typename Context, typename T, typename Enable = void>
+		struct serializer_t
+		{
+			static void _(const T& t, Context& context)
 			{
-				static void _(const T& t, Context& context)
-				{
-					static_assert(wrong_t<Context, T>::value, "missing serializer specialization");
-				}
-			};
-	}
+				static_assert(wrong_t<Context, T>::value, "missing serializer specialization");
+			}
+		};
 
 }
 

include/sqlpp11/simple_column.h

@@ -27,36 +27,37 @@
 #ifndef SQLPP_SIMPLE_COLUMN_H
 #define SQLPP_SIMPLE_COLUMN_H
 
-#include <sqlpp11/vendor/serializer.h>
+#include <sqlpp11/serializer.h>
+#include <sqlpp11/type_traits.h>
 
 namespace sqlpp
 {
-	namespace vendor
-	{
-		template<typename Column>
-			struct simple_column_t
-			{
-				Column _column;
-			};
+	template<typename Column>
+		struct simple_column_t
+		{
+			Column _column;
 
-		template<typename Context, typename Column>
-			struct serializer_t<Context, simple_column_t<Column>>
-			{
-				using T = simple_column_t<Column>;
+			using _traits = make_traits<no_value_t, ::sqlpp::tag::noop>;
+			using _recursive_traits = make_recursive_traits<>;
+		};
 
-				static Context& _(const T& t, Context& context)
-				{
-					context << t._column._get_name();
-					return context;
-				}
-			};
+	template<typename Context, typename Column>
+		struct serializer_t<Context, simple_column_t<Column>>
+		{
+			using T = simple_column_t<Column>;
 
-		template<typename Column>
-			simple_column_t<Column> simple_column(Column c)
+			static Context& _(const T& t, Context& context)
 			{
-				return {c};
+				context << t._column._get_name();
+				return context;
 			}
-	}
+		};
+
+	template<typename Column>
+		simple_column_t<Column> simple_column(Column c)
+		{
+			return {c};
+		}
 }
 
 #endif

include/sqlpp11/single_table.h

@@ -0,0 +1,169 @@
+/*
+ * Copyright (c) 2013-2014, Roland Bock
+ * All rights reserved.
+ * 
+ * Redistribution and use in source and binary forms, with or without modification,
+ * are permitted provided that the following conditions are met:
+ * 
+ *   Redistributions of source code must retain the above copyright notice, this
+ *   list of conditions and the following disclaimer.
+ * 
+ *   Redistributions in binary form must reproduce the above copyright notice, this
+ *   list of conditions and the following disclaimer in the documentation and/or
+ *   other materials provided with the distribution.
+ * 
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR
+ * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+ * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef SQLPP_SINGLE_TABLE_H
+#define SQLPP_SINGLE_TABLE_H
+
+#include <sqlpp11/type_traits.h>
+#include <sqlpp11/no_value.h>
+#include <sqlpp11/no_data.h>
+#include <sqlpp11/serializer.h>
+#include <sqlpp11/prepared_insert.h>
+#include <sqlpp11/detail/type_set.h>
+
+namespace sqlpp
+{
+	// A SINGLE TABLE DATA
+	template<typename Database, typename Table>
+		struct single_table_data_t
+		{
+			single_table_data_t(Table table):
+				_table(table)
+			{}
+
+			single_table_data_t(const single_table_data_t&) = default;
+			single_table_data_t(single_table_data_t&&) = default;
+			single_table_data_t& operator=(const single_table_data_t&) = default;
+			single_table_data_t& operator=(single_table_data_t&&) = default;
+			~single_table_data_t() = default;
+
+			Table _table;
+		};
+
+	// A SINGLE TABLE
+	template<typename Database, typename Table>
+		struct single_table_t
+		{
+			using _traits = make_traits<no_value_t, ::sqlpp::tag::single_table>;
+			using _recursive_traits = make_recursive_traits<Table>;
+
+			static_assert(is_table_t<Table>::value, "argument has to be a table");
+			static_assert(required_tables_of<Table>::size::value == 0, "table depends on another table");
+
+			using _data_t = single_table_data_t<Database, Table>;
+
+			struct _name_t {};
+
+			// Member implementation with data and methods
+			template <typename Policies>
+				struct _impl_t
+				{
+					_data_t _data;
+				};
+
+			// Member template for adding the named member to a statement
+			template<typename Policies>
+				struct _member_t
+				{
+					using _data_t = single_table_data_t<Database, Table>;
+
+					_impl_t<Policies> from;
+					_impl_t<Policies>& operator()() { return from; }
+					const _impl_t<Policies>& operator()() const { return from; }
+
+					template<typename T>
+						static auto _get_member(T t) -> decltype(t.from)
+						{
+							return t.from;
+						}
+				};
+
+			// Additional methods for the statement
+			template<typename Policies>
+				struct _methods_t
+				{
+					static void _check_consistency() {}
+				};
+
+		};
+
+	// NO INTO YET
+	struct no_single_table_t
+	{
+		using _traits = make_traits<no_value_t, ::sqlpp::tag::noop>;
+		using _recursive_traits = make_recursive_traits<>;
+
+		// Data
+		using _data_t = no_data_t;
+
+		// Member implementation with data and methods
+		template<typename Policies>
+			struct _impl_t
+			{
+				_data_t _data;
+			};
+
+		// Member template for adding the named member to a statement
+		template<typename Policies>
+			struct _member_t
+			{
+				using _data_t = no_data_t;
+
+				_impl_t<Policies> no_from;
+				_impl_t<Policies>& operator()() { return no_from; }
+				const _impl_t<Policies>& operator()() const { return no_from; }
+
+				template<typename T>
+					static auto _get_member(T t) -> decltype(t.no_from)
+					{
+						return t.no_from;
+					}
+			};
+
+		template<typename Policies>
+			struct _methods_t
+			{
+				using _database_t = typename Policies::_database_t;
+				template<typename T>
+					using _new_statement_t = typename Policies::template _new_statement_t<no_single_table_t, T>;
+
+				static void _check_consistency() {}
+
+				template<typename... Args>
+					auto from(Args... args)
+					-> _new_statement_t<single_table_t<void, Args...>>
+					{
+						return { *static_cast<typename Policies::_statement_t*>(this), single_table_data_t<void, Args...>{args...} };
+					}
+			};
+	};
+
+	// Interpreters
+	template<typename Context, typename Database, typename Table>
+		struct serializer_t<Context, single_table_data_t<Database, Table>>
+		{
+			using T = single_table_data_t<Database, Table>;
+
+			static Context& _(const T& t, Context& context)
+			{
+				serialize(t._table, context);
+				return context;
+			}
+		};
+
+}
+
+#endif

include/sqlpp11/some.h

@@ -32,16 +32,11 @@
 
 namespace sqlpp
 {
-	namespace vendor
-	{
-		template<typename Select>
+	template<typename Select>
 		struct some_t
 		{
-			struct _value_type: public Select::_value_type::_base_value_type
-			{
-				using _is_expression = std::false_type;
-				using _is_multi_expression = std::true_type; // must not be named or used with +,-,*,/, etc
-			};
+			using _traits = make_traits<value_type_of<Select>, ::sqlpp::tag::multi_expression>;
+			using _recursive_traits = make_recursive_traits<Select>;
 
 			struct _name_t
 			{
@@ -54,7 +49,6 @@ namespace sqlpp
 						const T& operator()() const { return some; }
 					};
 			};
-			using _table_set = typename Select::_table_set;
 
 			some_t(Select select):
 				_select(select)
@@ -68,30 +62,26 @@ namespace sqlpp
 
 			Select _select;
 		};
-	}
 
-	namespace vendor
-	{
-		template<typename Context, typename Select>
-			struct serializer_t<Context, vendor::some_t<Select>>
+	template<typename Context, typename Select>
+		struct serializer_t<Context, some_t<Select>>
+		{
+			using T = some_t<Select>;
+
+			static Context& _(const T& t, Context& context)
 			{
-				using T = vendor::some_t<Select>;
-
-				static Context& _(const T& t, Context& context)
-				{
-					context << "SOME(";
-					serialize(t._select, context);
-					context << ")";
-					return context;
-				}
-			};
-	}
+				context << "SOME(";
+				serialize(t._select, context);
+				context << ")";
+				return context;
+			}
+		};
 
 	template<typename T>
-		auto some(T t) -> typename vendor::some_t<vendor::wrap_operand_t<T>>
+		auto some(T t) -> some_t<wrap_operand_t<T>>
 		{
-			static_assert(is_select_t<vendor::wrap_operand_t<T>>::value, "some() requires a single column select expression as argument");
-			static_assert(is_value_t<vendor::wrap_operand_t<T>>::value, "some() requires a single column select expression as argument");
+			static_assert(is_select_t<wrap_operand_t<T>>::value, "some() requires a single column select expression as argument");
+			static_assert(is_expression_t<wrap_operand_t<T>>::value, "some() requires a single column select expression as argument");
 			return { t };
 		}
 

include/sqlpp11/sort_order.h

@@ -28,6 +28,7 @@
 #define SQLPP_SORT_ORDER_H
 
 #include <sqlpp11/detail/type_set.h>
+#include <sqlpp11/no_value.h>
 
 namespace sqlpp
 {
@@ -40,36 +41,33 @@ namespace sqlpp
 	template<typename Expression, sort_type SortType>
 		struct sort_order_t
 		{
-			using _is_sort_order = std::true_type;
-			using _table_set = typename Expression::_table_set;
+			using _traits = make_traits<no_value_t,  tag::sort_order, sqlpp::tag::expression>;
+			using _recursive_traits = make_recursive_traits<Expression>;
 
 			Expression _expression;
 		};
 
-	namespace vendor
-	{
-		template<typename Context, typename Expression, sort_type SortType>
-			struct serializer_t<Context, sort_order_t<Expression, SortType>>
+	template<typename Context, typename Expression, sort_type SortType>
+		struct serializer_t<Context, sort_order_t<Expression, SortType>>
+		{
+			using T = sort_order_t<Expression, SortType>;
+
+			static Context& _(const T& t, Context& context)
 			{
-				using T = sort_order_t<Expression, SortType>;
-
-				static Context& _(const T& t, Context& context)
+				serialize(t._expression, context);
+				switch(SortType)
 				{
-					serialize(t._expression, context);
-					switch(SortType)
-					{
-					case sort_type::asc:
-						context << " ASC";
-						break;
-					default:
-						context << " DESC";
-						break;
-					}
-					return context;
+				case sort_type::asc:
+					context << " ASC";
+					break;
+				default:
+					context << " DESC";
+					break;
 				}
-			};
+				return context;
+			}
+		};
 
-	}
 }
 
 #endif

include/sqlpp11/statement.h

@@ -0,0 +1,237 @@
+/*
+ * Copyright (c) 2013-2014, Roland Bock
+ * All rights reserved.
+ * 
+ * Redistribution and use in source and binary forms, with or without modification,
+ * are permitted provided that the following conditions are met:
+ * 
+ *   Redistributions of source code must retain the above copyright notice, this
+ *   list of conditions and the following disclaimer.
+ * 
+ *   Redistributions in binary form must reproduce the above copyright notice, this
+ *   list of conditions and the following disclaimer in the documentation and/or
+ *   other materials provided with the distribution.
+ * 
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR
+ * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+ * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef SQLPP_STATEMENT_H
+#define SQLPP_STATEMENT_H
+
+#include <sqlpp11/result.h>
+#include <sqlpp11/parameter_list.h>
+#include <sqlpp11/prepared_select.h>
+#include <sqlpp11/serialize.h>
+#include <sqlpp11/noop.h>
+#include <sqlpp11/policy_update.h>
+#include <sqlpp11/serializer.h>
+
+#include <sqlpp11/detail/get_last.h>
+#include <sqlpp11/detail/pick_arg.h>
+
+namespace sqlpp
+{
+	template<typename Db, typename... Policies>
+		struct statement_t;
+
+	namespace detail
+	{
+		template<typename Db = void, typename... Policies>
+			struct statement_policies_t
+			{
+				using _database_t = Db;
+				using _statement_t = statement_t<Db, Policies...>;
+
+				template<typename Needle, typename Replacement>
+					struct _policies_update_t
+					{
+						static_assert(detail::is_element_of<Needle, make_type_set_t<Policies...>>::value, "policies update for non-policy class detected");
+						using type =  statement_t<Db, policy_update_t<Policies, Needle, Replacement>...>;
+					};
+
+				template<typename Needle, typename Replacement>
+					using _new_statement_t = typename _policies_update_t<Needle, Replacement>::type;
+
+				using _all_required_tables = detail::make_joined_set_t<required_tables_of<Policies>...>;
+				using _all_provided_tables = detail::make_joined_set_t<provided_tables_of<Policies>...>;
+				using _all_extra_tables = detail::make_joined_set_t<extra_tables_of<Policies>...>;
+
+				using _known_tables = detail::make_joined_set_t<_all_provided_tables, _all_extra_tables>;
+
+				template<typename Expression>
+					using _no_unknown_tables = detail::is_subset_of<required_tables_of<Expression>, _known_tables>;
+
+				// The tables not covered by the from.
+				using _required_tables = detail::make_difference_set_t<
+					_all_required_tables,
+					_all_provided_tables // Hint: extra_tables are not used here because they are just a helper for dynamic .add_*()
+						>;
+
+				using _result_type_provider = detail::get_last_if<is_return_value_t, noop, Policies...>;
+
+				struct _result_methods_t: public _result_type_provider::template _result_methods_t<statement_policies_t>
+				{};
+
+
+				// A select can be used as a pseudo table if
+				//   - at least one column is selected
+				//   - the select is complete (leaks no tables)
+				using _can_be_used_as_table = typename std::conditional<
+					is_select_column_list_t<_result_type_provider>::value and _required_tables::size::value == 0,
+					std::true_type,
+					std::false_type
+						>::type;
+
+				using _value_type = typename std::conditional<
+					detail::none_t<is_missing_t<Policies>::value...>::value,
+					value_type_of<_result_type_provider>,
+					no_value_t // if a required statement part is missing (e.g. columns in a select), then the statement cannot be used as a value
+						>::type;
+
+				using _is_expression = typename std::conditional<
+					std::is_same<_value_type, no_value_t>::value, 
+					std::false_type, 
+					std::true_type>::type;
+
+				using _traits = make_traits<_value_type>;
+
+				struct _recursive_traits
+				{
+					using _required_tables = statement_policies_t::_required_tables;
+					using _provided_tables = detail::type_set<>;
+					using _extra_tables = detail::type_set<>;
+					using _parameters = detail::make_parameter_tuple_t<parameters_of<Policies>...>;
+				};
+			};
+	}
+
+	template<typename Db,
+		typename... Policies
+			>
+			struct statement_t:
+				public Policies::template _member_t<detail::statement_policies_t<Db, Policies...>>...,
+				public detail::statement_policies_t<Db, Policies...>::_value_type::template expression_operators<statement_t<Db, Policies...>>,
+				public detail::statement_policies_t<Db, Policies...>::_result_methods_t,
+				public Policies::template _methods_t<detail::statement_policies_t<Db, Policies...>>...
+	{
+		using _policies_t = typename detail::statement_policies_t<Db, Policies...>;
+
+		using _traits = make_traits<value_type_of<_policies_t>, ::sqlpp::tag::select, tag::expression_if<typename _policies_t::_is_expression>, tag::named_expression_if<typename _policies_t::_is_expression>>;
+		using _recursive_traits = typename _policies_t::_recursive_traits;
+
+		using _result_type_provider = typename _policies_t::_result_type_provider;
+
+		using _requires_braces = std::true_type;
+
+		using _name_t = typename _result_type_provider::_name_t;
+
+		// Constructors
+		statement_t()
+		{}
+
+		template<typename Statement, typename Term>
+			statement_t(Statement statement, Term term):
+				Policies::template _member_t<_policies_t>{
+					typename Policies::template _impl_t<_policies_t>{
+						detail::pick_arg<typename Policies::template _member_t<_policies_t>>(statement, term)
+					}}...
+		//Policies::template _member_t<_policies_t>{{detail::pick_arg<typename Policies::template _member_t<_policies_t>>(statement, term)}}...
+		{}
+
+		statement_t(const statement_t& r) = default;
+		statement_t(statement_t&& r) = default;
+		statement_t& operator=(const statement_t& r) = default;
+		statement_t& operator=(statement_t&& r) = default;
+		~statement_t() = default;
+
+		static constexpr size_t _get_static_no_of_parameters()
+		{
+			return std::tuple_size<parameters_of<statement_t>>::value;
+		}
+
+		size_t _get_no_of_parameters() const
+		{
+			return _get_static_no_of_parameters();
+		}
+
+		static void _check_consistency()
+		{
+			static_assert(not required_tables_of<_policies_t>::size::value, "one sub expression requires tables which are otherwise not known in the statement");
+
+			using swallow = int[]; 
+			(void) swallow{(Policies::template _methods_t<detail::statement_policies_t<Db, Policies...>>::_check_consistency(), 0)...};
+		}
+
+
+	};
+
+	template<typename Context, typename Database, typename... Policies>
+		struct serializer_t<Context, statement_t<Database, Policies...>>
+		{
+			using T = statement_t<Database, Policies...>;
+			using P = ::sqlpp::detail::statement_policies_t<Database, Policies...>;
+
+			static Context& _(const T& t, Context& context)
+			{
+				using swallow = int[]; 
+				(void) swallow{(serialize(static_cast<const typename Policies::template _member_t<P>&>(t)()._data, context), 0)...};
+
+				return context;
+			}
+		};
+
+	template<typename NameData>
+		struct statement_name_t
+		{
+			using _traits = make_traits<no_value_t, ::sqlpp::tag::noop>;
+			using _recursive_traits = make_recursive_traits<>;
+
+			// Data
+			using _data_t = NameData;
+
+			// Member implementation with data and methods
+			template<typename Policies>
+				struct _impl_t
+				{
+					_data_t _data;
+				};
+
+			// Member template for adding the named member to a statement
+			template<typename Policies>
+				struct _member_t
+				{
+					using _data_t = NameData;
+
+					_impl_t<Policies> statement_name;
+					_impl_t<Policies>& operator()() { return statement_name; }
+					const _impl_t<Policies>& operator()() const { return statement_name; }
+
+					template<typename T>
+						static auto _get_member(T t) -> decltype(t.statement_name)
+						{
+							return t.statement_name;
+						}
+				};
+
+			// Additional methods for the statement
+			template<typename Policies>
+				struct _methods_t
+				{
+					static void _check_consistency() {}
+				};
+		};
+
+}
+
+#endif
+
+

include/sqlpp11/sum.h

@@ -31,78 +31,71 @@
 
 namespace sqlpp
 {
-	namespace vendor
+	template<typename Flag, typename Expr>
+		struct sum_t: public value_type_of<Expr>::template expression_operators<sum_t<Flag, Expr>>,
+		public alias_operators<sum_t<Flag, Expr>>
 	{
-		template<typename Flag, typename Expr>
-		struct sum_t: public Expr::_value_type::template expression_operators<sum_t<Flag, Expr>>
+		using _traits = make_traits<value_type_of<Expr>, ::sqlpp::tag::expression, ::sqlpp::tag::named_expression>;
+		using _recursive_traits = make_recursive_traits<Expr>;
+
+		static_assert(is_noop<Flag>::value or std::is_same<sqlpp::distinct_t, Flag>::value, "sum() used with flag other than 'distinct'");
+		static_assert(is_numeric_t<Expr>::value, "sum() requires a numeric expression as argument");
+
+		struct _name_t
 		{
-			static_assert(is_noop<Flag>::value or std::is_same<sqlpp::distinct_t, Flag>::value, "sum() used with flag other than 'distinct'");
-			static_assert(is_numeric_t<Expr>::value, "sum() requires a numeric expression as argument");
-
-			struct _value_type: public Expr::_value_type::_base_value_type
-			{
-				using _is_named_expression = std::true_type;
-			};
-
-			struct _name_t
-			{
-				static constexpr const char* _get_name() { return "SUM"; }
-				template<typename T>
-					struct _member_t
-					{
-						T sum;
-						T& operator()() { return sum; }
-						const T& operator()() const { return sum; }
-					};
-			};
-
-			sum_t(Expr expr):
-				_expr(expr)
-			{}
-
-			sum_t(const sum_t&) = default;
-			sum_t(sum_t&&) = default;
-			sum_t& operator=(const sum_t&) = default;
-			sum_t& operator=(sum_t&&) = default;
-			~sum_t() = default;
-
-			Expr _expr;
-		};
-	}
-
-	namespace vendor
-	{
-		template<typename Context, typename Flag, typename Expr>
-			struct serializer_t<Context, vendor::sum_t<Flag, Expr>>
-			{
-				using T = vendor::sum_t<Flag, Expr>;
-
-				static Context& _(const T& t, Context& context)
+			static constexpr const char* _get_name() { return "SUM"; }
+			template<typename T>
+				struct _member_t
 				{
-					context << "SUM(";
-					if (std::is_same<sqlpp::distinct_t, Flag>::value)
-					{
-						serialize(Flag(), context);
-						context << ' ';
-					}
-					serialize(t._expr, context);
-					context << ")";
-					return context;
+					T sum;
+					T& operator()() { return sum; }
+					const T& operator()() const { return sum; }
+				};
+		};
+
+		sum_t(Expr expr):
+			_expr(expr)
+		{}
+
+		sum_t(const sum_t&) = default;
+		sum_t(sum_t&&) = default;
+		sum_t& operator=(const sum_t&) = default;
+		sum_t& operator=(sum_t&&) = default;
+		~sum_t() = default;
+
+		Expr _expr;
+	};
+
+	template<typename Context, typename Flag, typename Expr>
+		struct serializer_t<Context, sum_t<Flag, Expr>>
+		{
+			using T = sum_t<Flag, Expr>;
+
+			static Context& _(const T& t, Context& context)
+			{
+				context << "SUM(";
+				if (std::is_same<sqlpp::distinct_t, Flag>::value)
+				{
+					serialize(Flag(), context);
+					context << ' ';
 				}
-			};
-	}
+				serialize(t._expr, context);
+				context << ")";
+				return context;
+			}
+		};
 
 	template<typename T>
-		auto sum(T t) -> typename vendor::sum_t<vendor::noop, vendor::wrap_operand_t<T>>
+		auto sum(T t) -> sum_t<noop, wrap_operand_t<T>>
 		{
-			static_assert(is_numeric_t<vendor::wrap_operand_t<T>>::value, "sum() requires a numeric expression as argument");
+			static_assert(is_numeric_t<wrap_operand_t<T>>::value, "sum() requires a numeric expression as argument");
 			return { t };
 		}
 
 	template<typename T>
-		auto sum(const sqlpp::distinct_t&, T t) -> typename vendor::sum_t<sqlpp::distinct_t, vendor::wrap_operand_t<T>>
+		auto sum(const sqlpp::distinct_t&, T t) -> sum_t<sqlpp::distinct_t, wrap_operand_t<T>>
 		{
-			static_assert(is_numeric_t<vendor::wrap_operand_t<T>>::value, "sum() requires a numeric expression as argument");
+			static_assert(is_numeric_t<wrap_operand_t<T>>::value, "sum() requires a numeric expression as argument");
 			return { t };
 		}
 

include/sqlpp11/table.h

@@ -40,16 +40,24 @@ namespace sqlpp
 	struct table_base_t {};
 
 	template<typename Table, typename... ColumnSpec>
-	struct table_t: public table_base_t, public ColumnSpec::_name_t::template _member_t<column_t<Table, ColumnSpec>>...
+		struct table_t: public table_base_t, public ColumnSpec::_name_t::template _member_t<column_t<Table, ColumnSpec>>...
 	{
-		using _table_set = detail::type_set<Table>; // Hint need a type_set here to be similar to a join (which always represents more than one table)
+		using _traits = make_traits<no_value_t, tag::table>;
+
+		struct _recursive_traits
+		{
+			using _parameters = std::tuple<>;
+			using _required_tables = detail::type_set<>;
+			using _provided_tables = detail::type_set<Table>;
+			using _extra_tables = detail::type_set<>;
+		};
+
 		static_assert(sizeof...(ColumnSpec), "at least one column required per table");
 		using _required_insert_columns = typename detail::make_type_set_if<require_insert_t, column_t<Table, ColumnSpec>...>::type;
 		using _column_tuple_t = std::tuple<column_t<Table, ColumnSpec>...>;
 		template<typename AliasProvider>
 			using _alias_t = table_alias_t<AliasProvider, Table, ColumnSpec...>;
 
-		using _is_table = std::true_type;
 
 		template<typename T>
 			join_t<inner_join_t, Table, T> join(T t)
@@ -93,22 +101,19 @@ namespace sqlpp
 		}
 	};
 
-	namespace vendor
-	{
-		template<typename Context, typename X>
-			struct serializer_t<Context, X, typename std::enable_if<std::is_base_of<table_base_t, X>::value and not is_pseudo_table_t<X>::value, void>::type>
+	template<typename Context, typename X>
+		struct serializer_t<Context, X, typename std::enable_if<std::is_base_of<table_base_t, X>::value and not is_pseudo_table_t<X>::value, void>::type>
+		{
+			using T = X;
+
+			static Context& _(const T& t, Context& context)
 			{
-				using T = X;
-
-				static Context& _(const T& t, Context& context)
-				{
-					context << T::_name_t::_get_name();
-					return context;
-				}
-			};
+				context << T::_name_t::_get_name();
+				return context;
+			}
+		};
 
 
-	}
 }
 
 #endif

include/sqlpp11/table_alias.h

@@ -35,22 +35,22 @@
 
 namespace sqlpp
 {
-	struct table_alias_base_t {};
-
 	template<typename AliasProvider, typename Table, typename... ColumnSpec>
-		struct table_alias_t: public table_alias_base_t, public ColumnSpec::_name_t::template _member_t<column_t<AliasProvider, ColumnSpec>>...
+		struct table_alias_t: public ColumnSpec::_name_t::template _member_t<column_t<AliasProvider, ColumnSpec>>...
 	{
 		//FIXME: Need to add join functionality
-		using _is_table = std::true_type;
-		using _table_set = detail::type_set<AliasProvider>;
+		using _traits = make_traits<value_type_of<Table>, tag::table, tag::alias, tag::named_expression_if<is_expression_t<Table>>>;
 
-		struct _value_type: Table::_value_type
+		struct _recursive_traits
 		{
-			using _is_expression = std::false_type;
-			using _is_named_expression = copy_type_trait<Table, is_value_t>;
-			using _is_alias = std::true_type;
+			using _parameters = std::tuple<>;
+			using _required_tables = detail::type_set<>;
+			using _provided_tables = detail::type_set<AliasProvider>;
+			using _extra_tables = detail::type_set<>;
 		};
 
+		static_assert(required_tables_of<Table>::size::value == 0, "table aliases must not depend on external tables");
+
 		using _name_t = typename AliasProvider::_name_t;
 		using _column_tuple_t = std::tuple<column_t<Table, ColumnSpec>...>;
 
@@ -61,23 +61,20 @@ namespace sqlpp
 		Table _table;
 	};
 
-	namespace vendor
-	{
-		template<typename Context, typename X>
-			struct serializer_t<Context, X, typename std::enable_if<std::is_base_of<table_alias_base_t, X>::value, void>::type>
+	template<typename Context, typename AliasProvider, typename Table, typename... ColumnSpec>
+		struct serializer_t<Context, table_alias_t<AliasProvider, Table, ColumnSpec...>>
+		{
+			using T = table_alias_t<AliasProvider, Table, ColumnSpec...>;
+
+			static Context& _(const T& t, Context& context)
 			{
-				using T = X;
+				context << "(";
+				serialize(t._table, context);
+				context << ") AS " << T::_name_t::_get_name();
+				return context;
+			}
+		};
 
-				static Context& _(const T& t, Context& context)
-				{
-					context << "(";
-					serialize(t._table, context);
-					context << ") AS " << T::_name_t::_get_name();
-					return context;
-				}
-			};
-
-	}
 }
 
 #endif

include/sqlpp11/text.h

@@ -31,8 +31,8 @@
 #include <sqlpp11/basic_expression_operators.h>
 #include <sqlpp11/type_traits.h>
 #include <sqlpp11/exception.h>
-#include <sqlpp11/vendor/concat.h>
-#include <sqlpp11/vendor/like.h>
+#include <sqlpp11/concat.h>
+#include <sqlpp11/like.h>
 
 namespace sqlpp
 {
@@ -41,11 +41,7 @@ namespace sqlpp
 		// text value type
 		struct text
 		{
-			using _value_type = text;
-			using _base_value_type = text;
-			using _is_text = std::true_type;
-			using _is_value = std::true_type;
-			using _is_expression = std::true_type;
+			using _tag = ::sqlpp::tag::text;
 			using _cpp_value_type = std::string;
 
 			struct _parameter_t
@@ -55,12 +51,12 @@ namespace sqlpp
 				_parameter_t():
 					_value(""),
 					_is_null(true)
-					{}
+				{}
 
 				_parameter_t(const _cpp_value_type& value):
 					_value(value),
 					_is_null(false)
-					{}
+				{}
 
 				_parameter_t& operator=(const _cpp_value_type& value)
 				{
@@ -77,7 +73,7 @@ namespace sqlpp
 				}
 
 				bool is_null() const
-			 	{ 
+				{ 
 					return _is_null; 
 				}
 
@@ -100,111 +96,98 @@ namespace sqlpp
 			};
 
 			template<typename Db, bool NullIsTrivial = false>
-			struct _result_entry_t
-			{
-				_result_entry_t():
-					_is_valid(false),
-					_value_ptr(nullptr),
-					_len(0)
+				struct _result_entry_t
+				{
+					_result_entry_t():
+						_is_valid(false),
+						_value_ptr(nullptr),
+						_len(0)
 					{}
 
-				_result_entry_t(char* data, size_t len):
-					_is_valid(true),
-					_value_ptr(data),
-					_len(_value_ptr ? 0 : len)
-					{}
-
-				void assign(const char* data, size_t len)
-				{
-					_is_valid = true;
-					_value_ptr = data;
-					_len = _value_ptr ? len: 0;
-				}
-
-				void validate()
-				{
-					_is_valid = true;
-				}
-
-				void invalidate()
-				{
-					_is_valid = false;
-					_value_ptr = nullptr;
-					_len = 0;
-				}
-
-				bool operator==(const _cpp_value_type& rhs) const { return value() == rhs; }
-				bool operator!=(const _cpp_value_type& rhs) const { return not operator==(rhs); }
-
-				bool is_null() const
-			 	{ 
-					if (connector_assert_result_validity_t<Db>::value)
-						assert(_is_valid);
-					else if (not _is_valid)
-						throw exception("accessing is_null in non-existing row");
-					return _value_ptr == nullptr; 
-				}
-
-				_cpp_value_type value() const
-				{
-					const bool null_value = _value_ptr == nullptr and not NullIsTrivial and not connector_null_result_is_trivial_value_t<Db>::value;
-					if (connector_assert_result_validity_t<Db>::value)
+					void _validate()
 					{
-						assert(_is_valid);
-						assert(not null_value);
-					}
-					else
-					{
-						if (not _is_valid)
-							throw exception("accessing value in non-existing row");
-						if (null_value)
-							throw exception("accessing value of NULL field");
-					}
-					if (_value_ptr) 
-						return std::string(_value_ptr, _value_ptr + _len);
-					else
-						return "";
-				}
-
-				operator _cpp_value_type() const { return value(); }
-
-				template<typename Target>
-					void _bind(Target& target, size_t i)
-					{
-						target._bind_text_result(i, &_value_ptr, &_len);
+						_is_valid = true;
 					}
 
-			private:
-				bool _is_valid;
-				const char* _value_ptr;
-				size_t _len;
-			};
+					void _invalidate()
+					{
+						_is_valid = false;
+						_value_ptr = nullptr;
+						_len = 0;
+					}
+
+					bool operator==(const _cpp_value_type& rhs) const { return value() == rhs; }
+					bool operator!=(const _cpp_value_type& rhs) const { return not operator==(rhs); }
+
+					bool is_null() const
+					{ 
+						if (connector_assert_result_validity_t<Db>::value)
+							assert(_is_valid);
+						else if (not _is_valid)
+							throw exception("accessing is_null in non-existing row");
+						return _value_ptr == nullptr; 
+					}
+
+					_cpp_value_type value() const
+					{
+						const bool null_value = _value_ptr == nullptr and not NullIsTrivial and not connector_null_result_is_trivial_value_t<Db>::value;
+						if (connector_assert_result_validity_t<Db>::value)
+						{
+							assert(_is_valid);
+							assert(not null_value);
+						}
+						else
+						{
+							if (not _is_valid)
+								throw exception("accessing value in non-existing row");
+							if (null_value)
+								throw exception("accessing value of NULL field");
+						}
+						if (_value_ptr) 
+							return std::string(_value_ptr, _value_ptr + _len);
+						else
+							return "";
+					}
+
+					operator _cpp_value_type() const { return value(); }
+
+					template<typename Target>
+						void _bind(Target& target, size_t i)
+						{
+							target._bind_text_result(i, &_value_ptr, &_len);
+						}
+
+				private:
+					bool _is_valid;
+					const char* _value_ptr;
+					size_t _len;
+				};
 
 			template<typename T>
 				struct _is_valid_operand
-			{
-				static constexpr bool value = 
-					is_expression_t<T>::value // expressions are OK
-					and is_text_t<T>::value // the correct value type is required, of course
-					;
-			};
+				{
+					static constexpr bool value = 
+						is_expression_t<T>::value // expressions are OK
+						and is_text_t<T>::value // the correct value type is required, of course
+						;
+				};
 
 			template<typename Base>
 				struct expression_operators: public basic_expression_operators<Base, is_text_t>
 			{
 				template<typename T>
-					vendor::concat_t<Base, vendor::wrap_operand_t<T>> operator+(T t) const
+					concat_t<Base, wrap_operand_t<T>> operator+(T t) const
 					{
-						using rhs = vendor::wrap_operand_t<T>;
+						using rhs = wrap_operand_t<T>;
 						static_assert(_is_valid_operand<rhs>::value, "invalid rhs operand");
 
 						return { *static_cast<const Base*>(this), {t} };
 					}
 
 				template<typename T>
-					vendor::like_t<Base, vendor::wrap_operand_t<T>> like(T t) const
+					like_t<Base, wrap_operand_t<T>> like(T t) const
 					{
-						using rhs = vendor::wrap_operand_t<T>;
+						using rhs = wrap_operand_t<T>;
 						static_assert(_is_valid_operand<rhs>::value, "invalid argument for like()");
 
 						return { *static_cast<const Base*>(this), {t} };
@@ -213,23 +196,23 @@ namespace sqlpp
 
 			template<typename Base>
 				struct column_operators
-			{
-				template<typename T>
-					auto operator +=(T t) const -> vendor::assignment_t<Base, vendor::concat_t<Base, vendor::wrap_operand_t<T>>>
-					{
-						using rhs = vendor::wrap_operand_t<T>;
-						static_assert(_is_valid_operand<rhs>::value, "invalid rhs assignment operand");
+				{
+					template<typename T>
+						auto operator +=(T t) const -> assignment_t<Base, concat_t<Base, wrap_operand_t<T>>>
+						{
+							using rhs = wrap_operand_t<T>;
+							static_assert(_is_valid_operand<rhs>::value, "invalid rhs assignment operand");
 
-						return { *static_cast<const Base*>(this), { *static_cast<const Base*>(this), rhs{t} } };
-					}
-			};
+							return { *static_cast<const Base*>(this), { *static_cast<const Base*>(this), rhs{t} } };
+						}
+				};
 		};
 
 		template<typename Db, bool TrivialIsNull>
-		inline std::ostream& operator<<(std::ostream& os, const text::_result_entry_t<Db, TrivialIsNull>& e)
-		{
-			return os << e.value();
-		}
+			inline std::ostream& operator<<(std::ostream& os, const text::_result_entry_t<Db, TrivialIsNull>& e)
+			{
+				return os << e.value();
+			}
 	}
 
 	using text = detail::text;

include/sqlpp11/transaction.h

@@ -35,56 +35,56 @@ namespace sqlpp
 	static constexpr bool report_auto_rollback = true;
 
 	template<typename Db>
-	class transaction_t
-	{
-		Db& _db;
-		const bool _report_unfinished_transaction;
-		bool _finished = false;
-
-	public:
-		transaction_t(Db& db, bool report_unfinished_transaction):
-			_db(db),
-			_report_unfinished_transaction(report_unfinished_transaction)
+		class transaction_t
 		{
-			_db.start_transaction();
-		}
+			Db& _db;
+			const bool _report_unfinished_transaction;
+			bool _finished = false;
 
-		transaction_t(const transaction_t&) = delete;
-		transaction_t(transaction_t&&) = default;
-		transaction_t& operator=(const transaction_t&) = delete;
-		transaction_t& operator=(transaction_t&&) = delete;
-
-		~transaction_t()
-		{
-			if (not _finished)
+		public:
+			transaction_t(Db& db, bool report_unfinished_transaction):
+				_db(db),
+				_report_unfinished_transaction(report_unfinished_transaction)
 			{
-				try
+				_db.start_transaction();
+			}
+
+			transaction_t(const transaction_t&) = delete;
+			transaction_t(transaction_t&&) = default;
+			transaction_t& operator=(const transaction_t&) = delete;
+			transaction_t& operator=(transaction_t&&) = delete;
+
+			~transaction_t()
+			{
+				if (not _finished)
 				{
-					_db.rollback_transaction(_report_unfinished_transaction);
-				}
-				catch(const std::exception& e)
-				{
-					_db.report_rollback_failure(std::string("auto rollback failed: ") + e.what());
-				}
-				catch(...)
-				{
-					_db.report_rollback_failure("auto rollback failed with unknown exception");
+					try
+					{
+						_db.rollback_transaction(_report_unfinished_transaction);
+					}
+					catch(const std::exception& e)
+					{
+						_db.report_rollback_failure(std::string("auto rollback failed: ") + e.what());
+					}
+					catch(...)
+					{
+						_db.report_rollback_failure("auto rollback failed with unknown exception");
+					}
 				}
 			}
-		}
 
-		void commit()
-		{
-			_finished = true;
-			_db.commit_transaction();
-		}
+			void commit()
+			{
+				_finished = true;
+				_db.commit_transaction();
+			}
 
-		void rollback()
-		{
-			_finished = true;
-			_db.rollback_transaction(false);
-		}
-	};
+			void rollback()
+			{
+				_finished = true;
+				_db.rollback_transaction(false);
+			}
+		};
 
 	template<typename Db>
 		transaction_t<Db> start_transaction(Db& db, bool report_unfinished_transaction = report_auto_rollback)

include/sqlpp11/tvin.h

@@ -31,16 +31,18 @@
 
 #include <sqlpp11/type_traits.h>
 #include <sqlpp11/serialize.h>
-#include <sqlpp11/vendor/serializer.h>
+#include <sqlpp11/serializer.h>
+#include <sqlpp11/wrap_operand.h>
 
 namespace sqlpp
 {
 	template<typename Operand>
 		struct tvin_t
 		{
+			using _traits = make_traits<value_type_of<Operand>, tag::expression>;
+			using _recursive_traits = make_recursive_traits<Operand>;
+
 			using _operand_t = Operand;
-			using _value_type = typename _operand_t::_value_type;
-			using _table_set = typename _operand_t::_table_set;
 
 			tvin_t(Operand operand): 
 				_value(operand)
@@ -56,34 +58,33 @@ namespace sqlpp
 				return _value._is_trivial();
 			}
 
-			_operand_t _value;
+			Operand _value;
 		};
 
-	namespace vendor
-	{
-		template<typename Context, typename Operand>
-			struct serializer_t<Context, tvin_t<Operand>>
+	template<typename Context, typename Operand>
+		struct serializer_t<Context, tvin_t<Operand>>
+		{
+			using T = tvin_t<Operand>;
+
+			static void _(const T& t, Context& context)
 			{
-				using T = tvin_t<Operand>;
+				static_assert(wrong_t<T>::value, "tvin() must not be used with anything but =, ==, != and !");
+			}
+		};
 
-				static void _(const T& t, Context& context)
-				{
-					static_assert(vendor::wrong_t<T>::value, "tvin() must not be used with anything but =, ==, != and !");
-				}
-			};
-	}
-
-	template<typename T>
+	template<typename Operand>
 		struct maybe_tvin_t
 		{
-			using _table_set = typename T::_table_set;
+			using _traits = make_traits<value_type_of<Operand>, tag::expression>;
+			using _recursive_traits = make_recursive_traits<Operand>;
+
 			static constexpr bool _is_trivial()
 			{
 				return false;
 			}
 
-			maybe_tvin_t(T t): 
-				_value(t)
+			maybe_tvin_t(Operand operand): 
+				_value(operand)
 			{}
 			maybe_tvin_t(const maybe_tvin_t&) = default;
 			maybe_tvin_t(maybe_tvin_t&&) = default;
@@ -91,20 +92,22 @@ namespace sqlpp
 			maybe_tvin_t& operator=(maybe_tvin_t&&) = default;
 			~maybe_tvin_t() = default;
 
-			T _value;
+			Operand _value;
 		};
 
-	template<typename T>
-		struct maybe_tvin_t<tvin_t<T>>
+	template<typename Operand>
+		struct maybe_tvin_t<tvin_t<Operand>>
 		{
-			using _table_set = typename T::_table_set;
+			using _traits = make_traits<value_type_of<Operand>, tag::expression>;
+			using _recursive_traits = make_recursive_traits<Operand>;
+
 			bool _is_trivial() const
 			{
 				return _value._is_trivial();
 			};
 
-			maybe_tvin_t(tvin_t<T> t): 
-				_value(t._value)
+			maybe_tvin_t(tvin_t<Operand> operand): 
+				_value(operand._value)
 			{}
 			maybe_tvin_t(const maybe_tvin_t&) = default;
 			maybe_tvin_t(maybe_tvin_t&&) = default;
@@ -112,38 +115,35 @@ namespace sqlpp
 			maybe_tvin_t& operator=(maybe_tvin_t&&) = default;
 			~maybe_tvin_t() = default;
 
-			typename tvin_t<T>::_operand_t _value;
+			typename tvin_t<Operand>::_operand_t _value;
 		};
 
-	namespace vendor
-	{
-		template<typename Context, typename Operand>
-			struct serializer_t<Context, maybe_tvin_t<Operand>>
-			{
-				using T = maybe_tvin_t<Operand>;
-
-				static Context& _(const T& t, Context& context)
-				{
-					if (t._is_trivial())
-					{
-						context << "NULL";
-					}
-					else
-					{
-						serialize(t._value, context);
-					}
-					return context;
-				}
-			};
-	}
-
-	template<typename T>
-		auto tvin(T t) -> tvin_t<typename vendor::wrap_operand<T>::type>
+	template<typename Context, typename Operand>
+		struct serializer_t<Context, maybe_tvin_t<Operand>>
 		{
-			using _operand_t = typename vendor::wrap_operand<T>::type;
-			static_assert(std::is_same<_operand_t, vendor::text_operand>::value
-				 	or not std::is_same<_operand_t, T>::value, "tvin() used with invalid type (only string and primitive types allowed)");
-			return {{t}};
+			using T = maybe_tvin_t<Operand>;
+
+			static Context& _(const T& t, Context& context)
+			{
+				if (t._is_trivial())
+				{
+					context << "NULL";
+				}
+				else
+				{
+					serialize(t._value, context);
+				}
+				return context;
+			}
+		};
+
+	template<typename Operand>
+		auto tvin(Operand operand) -> tvin_t<typename wrap_operand<Operand>::type>
+		{
+			using _operand_t = typename wrap_operand<Operand>::type;
+			static_assert(std::is_same<_operand_t, text_operand>::value
+					or not std::is_same<_operand_t, Operand>::value, "tvin() used with invalid type (only string and primitive types allowed)");
+			return {{operand}};
 		}
 
 }

include/sqlpp11/type_traits.h

@@ -28,7 +28,7 @@
 #define SQLPP_TYPE_TRAITS_H
 
 #include <type_traits>
-#include <sqlpp11/vendor/wrap_operand.h>
+#include <sqlpp11/detail/type_set.h>
 
 namespace sqlpp
 {
@@ -36,54 +36,71 @@ namespace sqlpp
 	namespace detail\
 	{\
 		template<typename T, typename Enable = void>\
-			struct is_##name##_impl: std::false_type {};\
+		struct is_##name##_impl: std::false_type {};\
 		template<typename T>\
-			struct is_##name##_impl<T, typename std::enable_if<std::is_same<typename T::_value_type::_is_##name, std::true_type>::value>::type>: std::true_type {};\
+		struct is_##name##_impl<T, typename std::enable_if<std::is_same<typename T::_value_type::_is_##name, std::true_type>::value>::type>: std::true_type {};\
 	}\
+	namespace tag\
+	{\
+		struct name{};\
+	};\
 	template<typename T>\
-		struct is_##name##_t: detail::is_##name##_impl<T> {};
+	using is_##name##_t = detail::is_element_of<tag::name, typename T::_traits::_tags>;
 
 #define SQLPP_IS_COLUMN_TRAIT_GENERATOR(name) \
 	namespace detail\
 	{\
 		template<typename T, typename Enable = void>\
-			struct name##_impl { using type = std::false_type; };\
+		struct name##_impl { using type = std::false_type; };\
 		template<typename T>\
-			struct name##_impl<T, typename std::enable_if<std::is_same<typename T::_column_type::_##name, std::true_type>::value>::type> { using type = std::true_type; };\
+		struct name##_impl<T, typename std::enable_if<std::is_same<typename T::_column_type::_##name, std::true_type>::value>::type> { using type = std::true_type; };\
 	}\
 	template<typename T>\
-		using name##_t = typename detail::name##_impl<T>::type;
+	using name##_t = typename detail::name##_impl<T>::type;
 
 #define SQLPP_TYPE_TRAIT_GENERATOR(name) \
 	namespace detail\
 	{\
 		template<typename T, typename Enable = void>\
-			struct name##_impl: std::false_type {};\
+		struct name##_impl: std::false_type {};\
 		template<typename T>\
-			struct name##_impl<T, typename std::enable_if<std::is_same<typename T::_##name, std::true_type>::value>::type>: std::true_type {};\
+		struct name##_impl<T, typename std::enable_if<std::is_same<typename T::_##name, std::true_type>::value>::type>: std::true_type {};\
 	}\
 	template<typename T>\
-		struct name##_t: detail::name##_impl<T> {};
+	struct name##_t: detail::name##_impl<T> {};
 
 #define SQLPP_CONNECTOR_TRAIT_GENERATOR(name) \
 	namespace detail\
 	{\
 		template<typename T, typename Enable = void>\
-			struct connector_##name##_impl: std::false_type {};\
+		struct connector_##name##_impl: std::false_type {};\
 		template<typename T>\
-			struct connector_##name##_impl<T, typename std::enable_if<std::is_same<typename T::_tags::_##name, std::true_type>::value>::type>: std::true_type {};\
+		struct connector_##name##_impl<T, typename std::enable_if<std::is_same<typename T::_tags::_##name, std::true_type>::value>::type>: std::true_type {};\
 	}\
 	template<typename T>\
-		struct connector_##name##_t: detail::connector_##name##_impl<T> {};
+	struct connector_##name##_t: detail::connector_##name##_impl<T> {};
 
 	SQLPP_IS_VALUE_TRAIT_GENERATOR(boolean);
-	SQLPP_IS_VALUE_TRAIT_GENERATOR(numeric);
 	SQLPP_IS_VALUE_TRAIT_GENERATOR(integral);
 	SQLPP_IS_VALUE_TRAIT_GENERATOR(floating_point);
+	template<typename T>
+		using is_numeric_t = detail::any_t<
+		detail::is_element_of<tag::integral, typename T::_traits::_tags>::value,
+		detail::is_element_of<tag::floating_point, typename T::_traits::_tags>::value>;
 	SQLPP_IS_VALUE_TRAIT_GENERATOR(text);
-	SQLPP_IS_VALUE_TRAIT_GENERATOR(value);
+	SQLPP_IS_VALUE_TRAIT_GENERATOR(wrapped_value);
 	SQLPP_IS_VALUE_TRAIT_GENERATOR(expression);
 	SQLPP_IS_VALUE_TRAIT_GENERATOR(named_expression);
+	namespace tag
+	{
+		template<typename C>
+			using named_expression_if = typename std::conditional<C::value, tag::named_expression, void>::type;
+	}
+	namespace tag
+	{
+		template<typename C>
+			using expression_if = typename std::conditional<C::value, tag::expression, void>::type;
+	}
 	SQLPP_IS_VALUE_TRAIT_GENERATOR(multi_expression);
 	SQLPP_IS_VALUE_TRAIT_GENERATOR(alias);
 	SQLPP_IS_VALUE_TRAIT_GENERATOR(select_flag);
@@ -94,41 +111,130 @@ namespace sqlpp
 	SQLPP_IS_COLUMN_TRAIT_GENERATOR(can_be_null);
 	SQLPP_IS_COLUMN_TRAIT_GENERATOR(trivial_value_is_null);
 
-	SQLPP_TYPE_TRAIT_GENERATOR(is_noop);
-	SQLPP_TYPE_TRAIT_GENERATOR(is_table);
-	SQLPP_TYPE_TRAIT_GENERATOR(is_join);
-	SQLPP_TYPE_TRAIT_GENERATOR(is_pseudo_table);
-	SQLPP_TYPE_TRAIT_GENERATOR(is_column);
-	SQLPP_TYPE_TRAIT_GENERATOR(is_select);
-	SQLPP_TYPE_TRAIT_GENERATOR(is_select_flag_list);
-	SQLPP_TYPE_TRAIT_GENERATOR(is_select_column_list);
-	SQLPP_TYPE_TRAIT_GENERATOR(is_from);
-	SQLPP_TYPE_TRAIT_GENERATOR(is_on);
-	SQLPP_TYPE_TRAIT_GENERATOR(is_dynamic);
-	SQLPP_TYPE_TRAIT_GENERATOR(is_where);
-	SQLPP_TYPE_TRAIT_GENERATOR(is_group_by);
-	SQLPP_TYPE_TRAIT_GENERATOR(is_having);
-	SQLPP_TYPE_TRAIT_GENERATOR(is_order_by);
-	SQLPP_TYPE_TRAIT_GENERATOR(is_limit);
-	SQLPP_TYPE_TRAIT_GENERATOR(is_offset);
-	SQLPP_TYPE_TRAIT_GENERATOR(is_using);
-	SQLPP_TYPE_TRAIT_GENERATOR(is_column_list);
-	SQLPP_TYPE_TRAIT_GENERATOR(is_multi_column);
-	SQLPP_TYPE_TRAIT_GENERATOR(is_value_list);
-	SQLPP_TYPE_TRAIT_GENERATOR(is_assignment);
-	SQLPP_TYPE_TRAIT_GENERATOR(is_update_list);
-	SQLPP_TYPE_TRAIT_GENERATOR(is_insert_list);
-	SQLPP_TYPE_TRAIT_GENERATOR(is_insert_value);
-	SQLPP_TYPE_TRAIT_GENERATOR(is_insert_value_list);
-	SQLPP_TYPE_TRAIT_GENERATOR(is_sort_order);
+	SQLPP_IS_VALUE_TRAIT_GENERATOR(noop);
+	SQLPP_IS_VALUE_TRAIT_GENERATOR(missing);
+	SQLPP_IS_VALUE_TRAIT_GENERATOR(return_value);
+	SQLPP_IS_VALUE_TRAIT_GENERATOR(table);
+	SQLPP_IS_VALUE_TRAIT_GENERATOR(join);
+	SQLPP_IS_VALUE_TRAIT_GENERATOR(pseudo_table);
+	SQLPP_IS_VALUE_TRAIT_GENERATOR(column);
+	SQLPP_IS_VALUE_TRAIT_GENERATOR(select);
+	SQLPP_IS_VALUE_TRAIT_GENERATOR(select_flag_list);
+	SQLPP_IS_VALUE_TRAIT_GENERATOR(select_column_list);
+	SQLPP_IS_VALUE_TRAIT_GENERATOR(from);
+	SQLPP_IS_VALUE_TRAIT_GENERATOR(single_table);
+	SQLPP_IS_VALUE_TRAIT_GENERATOR(into);
+	SQLPP_IS_VALUE_TRAIT_GENERATOR(extra_tables);
+	SQLPP_IS_VALUE_TRAIT_GENERATOR(on);
+	SQLPP_IS_VALUE_TRAIT_GENERATOR(where);
+	SQLPP_IS_VALUE_TRAIT_GENERATOR(group_by);
+	SQLPP_IS_VALUE_TRAIT_GENERATOR(having);
+	SQLPP_IS_VALUE_TRAIT_GENERATOR(order_by);
+	SQLPP_IS_VALUE_TRAIT_GENERATOR(limit);
+	SQLPP_IS_VALUE_TRAIT_GENERATOR(offset);
+	SQLPP_IS_VALUE_TRAIT_GENERATOR(using_);
+	SQLPP_IS_VALUE_TRAIT_GENERATOR(column_list);
+	SQLPP_IS_VALUE_TRAIT_GENERATOR(multi_column);
+	SQLPP_IS_VALUE_TRAIT_GENERATOR(value_list);
+	SQLPP_IS_VALUE_TRAIT_GENERATOR(assignment);
+	SQLPP_IS_VALUE_TRAIT_GENERATOR(update_list);
+	SQLPP_IS_VALUE_TRAIT_GENERATOR(insert_list);
+	SQLPP_IS_VALUE_TRAIT_GENERATOR(insert_value);
+	SQLPP_IS_VALUE_TRAIT_GENERATOR(insert_value_list);
+	SQLPP_IS_VALUE_TRAIT_GENERATOR(sort_order);
+	SQLPP_IS_VALUE_TRAIT_GENERATOR(parameter);
+
 	SQLPP_TYPE_TRAIT_GENERATOR(requires_braces);
-	SQLPP_TYPE_TRAIT_GENERATOR(is_parameter);
 
 	SQLPP_CONNECTOR_TRAIT_GENERATOR(null_result_is_trivial_value);
 	SQLPP_CONNECTOR_TRAIT_GENERATOR(assert_result_validity);
 
+	template<typename Database>
+		using is_database = typename std::conditional<std::is_same<Database, void>::value, std::false_type, std::true_type>::type;
+
 	template<typename T, template<typename> class IsTag>
 		using copy_type_trait = typename std::conditional<IsTag<T>::value, std::true_type, std::false_type>::type;
+
+	namespace detail
+	{
+		template<typename T>
+			struct value_type_of_impl
+			{
+				using type = typename T::_traits::_value_type;
+			};
+
+		template<typename T>
+			struct required_table_of_impl
+			{
+				using type = typename T::_recursive_traits::_required_tables;
+			};
+
+		template<typename T>
+			struct provided_table_of_impl
+			{
+				using type = typename T::_recursive_traits::_provided_tables;
+			};
+
+		template<typename T>
+			struct extra_table_of_impl
+			{
+				using type = typename T::_recursive_traits::_extra_tables;
+			};
+
+		template<typename T>
+			struct parameters_of_impl
+			{
+				using type = typename T::_recursive_traits::_parameters;
+			};
+
+		template<typename T>
+			struct name_of_impl
+			{
+				using type = typename T::_name_t;
+			};
+
+		template<typename... T>
+			struct make_parameter_tuple_impl
+			{
+				using type = decltype(std::tuple_cat(std::declval<T>()...));
+			};
+
+		template<typename... T>
+			using make_parameter_tuple_t = typename make_parameter_tuple_impl<T...>::type;
+	}
+	template<typename T>
+		using value_type_of = typename detail::value_type_of_impl<T>::type;
+
+	template<typename T>
+		using required_tables_of = typename detail::required_table_of_impl<T>::type;
+
+	template<typename T>
+		using provided_tables_of = typename detail::provided_table_of_impl<T>::type;
+
+	template<typename T>
+		using extra_tables_of = typename detail::extra_table_of_impl<T>::type;
+
+	template<typename T>
+		using parameters_of = typename detail::parameters_of_impl<T>::type;
+
+	template<typename T>
+		using name_of = typename detail::name_of_impl<T>::type;
+
+	template<typename ValueType, typename... Tags>
+		struct make_traits
+		{
+			using _value_type = ValueType;
+			using _tags = detail::make_type_set_t<typename ValueType::_tag, Tags...>;
+		};
+	template<typename... Arguments>
+		struct make_recursive_traits
+		{
+			using _required_tables = detail::make_joined_set_t<required_tables_of<Arguments>...>;
+			using _provided_tables = detail::make_joined_set_t<provided_tables_of<Arguments>...>;
+			using _extra_tables = detail::make_joined_set_t<extra_tables_of<Arguments>...>;
+			using _parameters = detail::make_parameter_tuple_t<parameters_of<Arguments>...>;
+		};
+
 }
 
 #endif

include/sqlpp11/update.h

@@ -27,181 +27,90 @@
 #ifndef SQLPP_UPDATE_H
 #define SQLPP_UPDATE_H
 
+#include <sqlpp11/statement.h>
+
 #include <sqlpp11/type_traits.h>
 #include <sqlpp11/parameter_list.h>
 #include <sqlpp11/prepared_update.h>
-#include <sqlpp11/vendor/single_table.h>
-#include <sqlpp11/vendor/update_list.h>
-#include <sqlpp11/vendor/noop.h>
-#include <sqlpp11/vendor/where.h>
-#include <sqlpp11/vendor/policy_update.h>
-#include <sqlpp11/detail/arg_selector.h>
+#include <sqlpp11/single_table.h>
+#include <sqlpp11/update_list.h>
+#include <sqlpp11/noop.h>
+#include <sqlpp11/where.h>
 
 namespace sqlpp
 {
-	template<typename Db,
-			typename... Policies
-				>
-		struct update_t;
+	struct update_name_t {};
 
-	namespace detail
+	struct update_t: public statement_name_t<update_name_t>
 	{
-		template<typename Db = void, 
-			typename Table = vendor::no_single_table_t,
-			typename UpdateList = vendor::no_update_list_t,
-			typename Where = vendor::no_where_t
-				>
-			struct update_policies_t
+		using _traits = make_traits<no_value_t, tag::return_value>;
+		struct _name_t {};
+
+		template<typename Policies>
+			struct _result_methods_t
 			{
-				using _database_t = Db;
-				using _table_t = Table;
-				using _update_list_t = UpdateList;
-				using _where_t = Where;
+				using _statement_t = typename Policies::_statement_t;
 
-				using _statement_t = update_t<Db, Table, UpdateList, Where>;
+				const _statement_t& _get_statement() const
+				{
+					return static_cast<const _statement_t&>(*this);
+				}
 
-				struct _methods_t:
-					public _update_list_t::template _methods_t<update_policies_t>,
-					public _where_t::template _methods_t<update_policies_t>
-				{};
-
-				template<typename Needle, typename Replacement, typename... Policies>
-					struct _policies_update_t
+				template<typename Db>
+					auto _run(Db& db) const -> decltype(db.update(this->_get_statement()))
 					{
-						using type =  update_t<Db, vendor::policy_update_t<Policies, Needle, Replacement>...>;
-					};
+						_statement_t::_check_consistency();
 
-				template<typename Needle, typename Replacement>
-					using _new_statement_t = typename _policies_update_t<Needle, Replacement, Table, UpdateList, Where>::type;
+						static_assert(_statement_t::_get_static_no_of_parameters() == 0, "cannot run update directly with parameters, use prepare instead");
+						return db.update(_get_statement());
+					}
 
-				using _known_tables = detail::make_joined_set_t<typename _table_t::_table_set>;
-
-				template<typename Expression>
-					using _no_unknown_tables = detail::is_subset_of<typename Expression::_table_set, _known_tables>;
+					 template<typename Db>
+					 auto _prepare(Db& db) const
+					 -> prepared_update_t<Db, _statement_t>
+					 {
+						 _statement_t::_check_consistency();
 
+						 return {{}, db.prepare_update(_get_statement())};
+					 }
 			};
-	}
+	};
 
-	template<typename Db, 
-			typename... Policies
-				>
-		struct update_t:
-			public detail::update_policies_t<Db, Policies...>::_methods_t
+
+	template<typename Context>
+		struct serializer_t<Context, update_name_t>
 		{
-			using _policies_t = typename detail::update_policies_t<Db, Policies...>;
-			using _database_t = typename _policies_t::_database_t;
-			using _table_t = typename _policies_t::_table_t;
-			using _update_list_t = typename _policies_t::_update_list_t;
-			using _where_t = typename _policies_t::_where_t;
+			using T = update_name_t;
 
-			using _is_dynamic = typename std::conditional<std::is_same<_database_t, void>::value, std::false_type, std::true_type>::type;
-
-			using _parameter_tuple_t = std::tuple<Policies...>;
-			using _parameter_list_t = typename make_parameter_list_t<update_t>::type;
-
-			static_assert(::sqlpp::detail::is_superset_of<typename _table_t::_table_set, typename _update_list_t::_table_set>::value, "updated columns do not match the table");
-			static_assert(::sqlpp::detail::is_superset_of<typename _table_t::_table_set, typename _where_t::_table_set>::value, "where condition does not match updated table");
-
-			// Constructors
-			update_t()
-			{}
-
-			template<typename Statement, typename T>
-				update_t(Statement s, T t):
-					_table(detail::arg_selector<_table_t>::_(s._table, t)),
-					_update_list(detail::arg_selector<_update_list_t>::_(s._update_list, t)),
-					_where(detail::arg_selector<_where_t>::_(s._where, t))
-			{}
-
-			update_t(const update_t&) = default;
-			update_t(update_t&&) = default;
-			update_t& operator=(const update_t&) = default;
-			update_t& operator=(update_t&&) = default;
-			~update_t() = default;
-
-			// run and prepare
-			static constexpr size_t _get_static_no_of_parameters()
+			static Context& _(const T& t, Context& context)
 			{
-				return _parameter_list_t::size::value;
+				context << "UPDATE ";
+
+				return context;
 			}
-
-			size_t _get_no_of_parameters() const
-			{
-				return _parameter_list_t::size::value;
-			}
-
-			template<typename A>
-				struct is_table_subset_of_table
-				{
-					static constexpr bool value = ::sqlpp::detail::is_subset_of<typename A::_table_set, typename _table_t::_table_set>::value;
-				};
-
-			void _check_consistency() const
-			{
-				static_assert(is_where_t<_where_t>::value, "cannot run update without having a where condition, use .where(true) to update all rows");
-
-				static_assert(is_table_subset_of_table<_update_list_t>::value, "updates require additional tables");
-				static_assert(is_table_subset_of_table<_where_t>::value, "where requires additional tables");
-			}
-
-			template<typename Database>
-				std::size_t _run(Database& db) const
-				{
-					_check_consistency();
-
-					static_assert(_get_static_no_of_parameters() == 0, "cannot run update directly with parameters, use prepare instead");
-					return db.update(*this);
-				}
-
-			template<typename Database>
-				auto _prepare(Database& db) const
-				-> prepared_update_t<Database, update_t>
-				{
-					_check_consistency();
-
-					return {{}, db.prepare_update(*this)};
-				}
-
-			_table_t _table;
-			_update_list_t _update_list;
-			_where_t _where;
 		};
 
-	namespace vendor
-	{
-		template<typename Context, typename Database, typename... Policies>
-			struct serializer_t<Context, update_t<Database, Policies...>>
-			{
-				using T = update_t<Database, Policies...>;
-
-				static Context& _(const T& t, Context& context)
-				{
-					context << "UPDATE ";
-					serialize(t._table, context);
-					serialize(t._update_list, context);
-					serialize(t._where, context);
-					return context;
-				}
-			};
-	}
-
-	template<typename Database, typename... Policies>
-		using make_update_t = typename detail::update_policies_t<Database, Policies...>::_statement_t;
+	template<typename Database>
+		using blank_update_t = statement_t<Database,
+					update_t,
+					no_single_table_t,
+					no_update_list_t,
+					no_where_t<true>
+						>;
 
 	template<typename Table>
 		constexpr auto update(Table table)
-		-> make_update_t<void, vendor::single_table_t<void, Table>>
+		-> decltype(blank_update_t<void>().from(table))
 		{
-			return { update_t<void>(), vendor::single_table_t<void, Table>{table} };
+			return { blank_update_t<void>().from(table) };
 		}
 
 	template<typename Database, typename Table>
 		constexpr auto  dynamic_update(const Database&, Table table)
-		-> make_update_t<Database, vendor::single_table_t<void, Table>>
+		-> decltype(blank_update_t<Database>().from(table))
 		{
-			return { update_t<Database>(), vendor::single_table_t<void, Table>{table} };
+			return { blank_update_t<Database>().from(table) };
 		}
-
 }
 
 #endif

include/sqlpp11/update_list.h

@@ -0,0 +1,223 @@
+/*
+ * Copyright (c) 2013-2014, Roland Bock
+ * All rights reserved.
+ * 
+ * Redistribution and use in source and binary forms, with or without modification,
+ * are permitted provided that the following conditions are met:
+ * 
+ *   Redistributions of source code must retain the above copyright notice, this
+ *   list of conditions and the following disclaimer.
+ * 
+ *   Redistributions in binary form must reproduce the above copyright notice, this
+ *   list of conditions and the following disclaimer in the documentation and/or
+ *   other materials provided with the distribution.
+ * 
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR
+ * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+ * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef SQLPP_UPDATE_LIST_H
+#define SQLPP_UPDATE_LIST_H
+
+#include <sqlpp11/type_traits.h>
+#include <sqlpp11/detail/type_set.h>
+#include <sqlpp11/interpret_tuple.h>
+#include <sqlpp11/interpretable_list.h>
+
+namespace sqlpp
+{
+	// UPDATE ASSIGNMENTS DATA
+	template<typename Database, typename... Assignments>
+		struct update_list_data_t
+		{
+			update_list_data_t(Assignments... assignments):
+				_assignments(assignments...)
+			{}
+
+			update_list_data_t(const update_list_data_t&) = default;
+			update_list_data_t(update_list_data_t&&) = default;
+			update_list_data_t& operator=(const update_list_data_t&) = default;
+			update_list_data_t& operator=(update_list_data_t&&) = default;
+			~update_list_data_t() = default;
+
+			std::tuple<Assignments...> _assignments;
+			interpretable_list_t<Database> _dynamic_assignments;
+		};
+
+	// UPDATE ASSIGNMENTS
+	template<typename Database, typename... Assignments>
+		struct update_list_t
+		{
+			using _traits = make_traits<no_value_t, ::sqlpp::tag::update_list>;
+			using _recursive_traits = make_recursive_traits<Assignments...>;
+			using _is_dynamic = is_database<Database>;
+
+			// Data
+			using _data_t = update_list_data_t<Database, Assignments...>;
+
+			// Member implementation with data and methods
+			template <typename Policies>
+				struct _impl_t
+				{
+					template<typename Assignment>
+						void add_ntc(Assignment assignment)
+						{
+							add<Assignment, std::false_type>(assignment);
+						}
+
+					template<typename Assignment, typename TableCheckRequired = std::true_type>
+						void add(Assignment assignment)
+						{
+							static_assert(_is_dynamic::value, "add must not be called for static from()");
+							static_assert(is_assignment_t<Assignment>::value, "invalid assignment argument in add()");
+							using _assigned_columns = detail::make_type_set_t<typename Assignments::_column_t...>;
+							static_assert(not detail::is_element_of<typename Assignment::_column_t, _assigned_columns>::value, "Must not assign value to column twice");
+							static_assert(sqlpp::detail::not_t<must_not_update_t, typename Assignment::_column_t>::value, "add() argument must not be updated");
+							static_assert(TableCheckRequired::value or Policies::template _no_unknown_tables<Assignment>::value, "assignment uses tables unknown to this statement in add()");
+
+							using ok = ::sqlpp::detail::all_t<
+								_is_dynamic::value, 
+								is_assignment_t<Assignment>::value>;
+
+							_add_impl(assignment, ok()); // dispatch to prevent compile messages after the static_assert
+						}
+
+				private:
+					template<typename Assignment>
+						void _add_impl(Assignment assignment, const std::true_type&)
+						{
+							return _data._dynamic_assignments.emplace_back(assignment);
+						}
+
+					template<typename Assignment>
+						void _add_impl(Assignment assignment, const std::false_type&);
+				public:
+					_data_t _data;
+				};
+
+			// Member template for adding the named member to a statement
+			template<typename Policies>
+				struct _member_t
+				{
+					using _data_t = update_list_data_t<Database, Assignments...>;
+
+					_impl_t<Policies> assignments;
+					_impl_t<Policies>& operator()() { return assignments; }
+					const _impl_t<Policies>& operator()() const { return assignments; }
+
+					template<typename T>
+						static auto _get_member(T t) -> decltype(t.assignments)
+						{
+							return t.assignments;
+						}
+				};
+
+			// Additional methods for the statement
+			template<typename Policies>
+				struct _methods_t
+				{
+					static void _check_consistency() {}
+				};
+		};
+
+	struct no_update_list_t
+	{
+		using _traits = make_traits<no_value_t, ::sqlpp::tag::where>;
+		using _recursive_traits = make_recursive_traits<>;
+
+		// Data
+		using _data_t = no_data_t;
+
+		// Member implementation with data and methods
+		template<typename Policies>
+			struct _impl_t
+			{
+				_data_t _data;
+			};
+
+		// Member template for adding the named member to a statement
+		template<typename Policies>
+			struct _member_t
+			{
+				using _data_t = no_data_t;
+
+				_impl_t<Policies> no_assignments;
+				_impl_t<Policies>& operator()() { return no_assignments; }
+				const _impl_t<Policies>& operator()() const { return no_assignments; }
+
+				template<typename T>
+					static auto _get_member(T t) -> decltype(t.no_assignments)
+					{
+						return t.no_assignments;
+					}
+			};
+
+		template<typename Policies>
+			struct _methods_t
+			{
+				using _database_t = typename Policies::_database_t;
+				template<typename T>
+					using _new_statement_t = typename Policies::template _new_statement_t<no_update_list_t, T>;
+
+				static void _check_consistency() {}
+
+				template<typename... Assignments>
+					auto set(Assignments... assignments)
+					-> _new_statement_t<update_list_t<void, Assignments...>>
+					{
+						static_assert(sizeof...(Assignments), "at least one assignment expression required in set()");
+						return _set_impl<void>(assignments...);
+					}
+
+				template<typename... Assignments>
+					auto dynamic_set(Assignments... assignments)
+					-> _new_statement_t<update_list_t<_database_t, Assignments...>>
+					{
+						static_assert(not std::is_same<_database_t, void>::value, "dynamic_set() must not be called in a static statement");
+						return _set_impl<_database_t>(assignments...);
+					}
+
+			private:
+				template<typename Database, typename... Assignments>
+					auto _set_impl(Assignments... assignments)
+					-> _new_statement_t<update_list_t<Database, Assignments...>>
+					{
+						static_assert(not ::sqlpp::detail::has_duplicates<Assignments...>::value, "at least one duplicate argument detected in set()");
+						static_assert(::sqlpp::detail::all_t<is_assignment_t<Assignments>::value...>::value, "at least one argument is not an assignment in set()");
+						static_assert(::sqlpp::detail::none_t<must_not_update_t<typename Assignments::_column_t>::value...>::value, "at least one assignment is prohibited by its column definition in set()");
+
+						using _column_required_tables = typename ::sqlpp::detail::make_joined_set<required_tables_of<typename Assignments::_column_t>...>::type;
+						static_assert(sizeof...(Assignments) ? (_column_required_tables::size::value == 1) : true, "set() contains assignments for columns from more than one table");
+
+						return { *static_cast<typename Policies::_statement_t*>(this), update_list_data_t<Database, Assignments...>{assignments...} };
+					}
+			};
+	};
+
+	// Interpreters
+	template<typename Context, typename Database, typename... Assignments>
+		struct serializer_t<Context, update_list_data_t<Database, Assignments...>>
+		{
+			using T = update_list_data_t<Database, Assignments...>;
+
+			static Context& _(const T& t, Context& context)
+			{
+				context << " SET ";
+				interpret_tuple(t._assignments, ",", context);
+				if (sizeof...(Assignments) and not t._dynamic_assignments.empty())
+					context << ',';
+				interpret_list(t._dynamic_assignments, ',', context);
+				return context;
+			}
+		};
+}
+
+#endif

include/sqlpp11/using.h

@@ -0,0 +1,207 @@
+/*
+ * Copyright (c) 2013-2014, Roland Bock
+ * All rights reserved.
+ * 
+ * Redistribution and use in source and binary forms, with or without modification,
+ * are permitted provided that the following conditions are met:
+ * 
+ *   Redistributions of source code must retain the above copyright notice, this
+ *   list of conditions and the following disclaimer.
+ * 
+ *   Redistributions in binary form must reproduce the above copyright notice, this
+ *   list of conditions and the following disclaimer in the documentation and/or
+ *   other materials provided with the distribution.
+ * 
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR
+ * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+ * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef SQLPP_USING_H
+#define SQLPP_USING_H
+
+#include <sqlpp11/type_traits.h>
+#include <sqlpp11/interpretable_list.h>
+#include <sqlpp11/interpret_tuple.h>
+#include <sqlpp11/detail/type_set.h>
+#include <sqlpp11/policy_update.h>
+
+namespace sqlpp
+{
+	// USING DATA
+	template<typename Database, typename... Tables>
+		struct using_data_t
+		{
+			using_data_t(Tables... tables):
+				_tables(tables...)
+			{}
+
+			using_data_t(const using_data_t&) = default;
+			using_data_t(using_data_t&&) = default;
+			using_data_t& operator=(const using_data_t&) = default;
+			using_data_t& operator=(using_data_t&&) = default;
+			~using_data_t() = default;
+
+			std::tuple<Tables...> _tables;
+			interpretable_list_t<Database> _dynamic_tables;
+		};
+
+	// USING
+	template<typename Database, typename... Tables>
+		struct using_t
+		{
+			using _traits = make_traits<no_value_t, ::sqlpp::tag::using_>;
+			using _recursive_traits = make_recursive_traits<Tables...>;
+
+			using _is_dynamic = is_database<Database>;
+
+			static_assert(_is_dynamic::value or sizeof...(Tables), "at least one table argument required in using()");
+
+			static_assert(not ::sqlpp::detail::has_duplicates<Tables...>::value, "at least one duplicate argument detected in using()");
+
+			static_assert(::sqlpp::detail::all_t<is_table_t<Tables>::value...>::value, "at least one argument is not an table in using()");
+
+			// Data
+			using _data_t = using_data_t<Database, Tables...>;
+
+			// Member implementation with data and methods
+			template <typename Policies>
+				struct _impl_t
+				{
+					template<typename Table>
+						void add(Table table)
+						{
+							static_assert(_is_dynamic::value, "add must not be called for static using()");
+							static_assert(is_table_t<Table>::value, "invalid table argument in add()");
+
+							using ok = ::sqlpp::detail::all_t<_is_dynamic::value, is_table_t<Table>::value>;
+
+							_add_impl(table, ok()); // dispatch to prevent compile messages after the static_assert
+						}
+
+				private:
+					template<typename Table>
+						void _add_impl(Table table, const std::true_type&)
+						{
+							return _data._dynamic_tables.emplace_back(table);
+						}
+
+					template<typename Table>
+						void _add_impl(Table table, const std::false_type&);
+
+				public:
+					_data_t _data;
+				};
+
+			// Member template for adding the named member to a statement
+			template<typename Policies>
+				struct _member_t
+				{
+					using _data_t = using_data_t<Database, Tables...>;
+
+					_impl_t<Policies> using_;
+					_impl_t<Policies>& operator()() { return using_; }
+					const _impl_t<Policies>& operator()() const { return using_; }
+
+					template<typename T>
+						static auto _get_member(T t) -> decltype(t.using_)
+						{
+							return t.using_;
+						}
+				};
+
+			// Additional methods for the statement
+			template<typename Policies>
+				struct _methods_t
+				{
+					static void _check_consistency() {}
+				};
+		};
+
+	// NO USING YET
+	struct no_using_t
+	{
+		using _traits = make_traits<no_value_t, ::sqlpp::tag::where>;
+		using _recursive_traits = make_recursive_traits<>;
+
+		// Data
+		using _data_t = no_data_t;
+
+		// Member implementation with data and methods
+		template<typename Policies>
+			struct _impl_t
+			{
+				_data_t _data;
+			};
+
+		// Member template for adding the named member to a statement
+		template<typename Policies>
+			struct _member_t
+			{
+				using _data_t = no_data_t;
+
+				_impl_t<Policies> no_using;
+				_impl_t<Policies>& operator()() { return no_using; }
+				const _impl_t<Policies>& operator()() const { return no_using; }
+
+				template<typename T>
+					static auto _get_member(T t) -> decltype(t.no_using)
+					{
+						return t.no_using;
+					}
+			};
+
+		template<typename Policies>
+			struct _methods_t
+			{
+				using _database_t = typename Policies::_database_t;
+				template<typename T>
+					using _new_statement_t = typename Policies::template _new_statement_t<no_using_t, T>;
+
+				static void _check_consistency() {}
+
+				template<typename... Args>
+					auto using_(Args... args)
+					-> _new_statement_t<using_t<void, Args...>>
+					{
+						return { *static_cast<typename Policies::_statement_t*>(this), using_data_t<void, Args...>{args...} };
+					}
+
+				template<typename... Args>
+					auto dynamic_using(Args... args)
+					-> _new_statement_t<using_t<_database_t, Args...>>
+					{
+						static_assert(not std::is_same<_database_t, void>::value, "dynamic_using must not be called in a static statement");
+						return { *static_cast<typename Policies::_statement_t*>(this), using_data_t<_database_t, Args...>{args...} };
+					}
+			};
+	};
+
+	// Interpreters
+	template<typename Context, typename Database, typename... Tables>
+		struct serializer_t<Context, using_data_t<Database, Tables...>>
+		{
+			using T = using_data_t<Database, Tables...>;
+
+			static Context& _(const T& t, Context& context)
+			{
+				if (sizeof...(Tables) == 0 and t._dynamic_tables.empty())
+					return context;
+				context << " USING ";
+				interpret_tuple(t._tables, ',', context);
+				if (sizeof...(Tables) and not t._dynamic_tables.empty())
+					context << ',';
+				interpret_list(t._dynamic_tables, ',', context);
+				return context;
+			}
+		};
+}
+
+#endif

include/sqlpp11/value_type.h

@@ -28,14 +28,11 @@
 #define SQLPP_VALUE_TYPE_H
 
 #include <type_traits>
-#include <sqlpp11/vendor/wrap_operand.h>
+#include <sqlpp11/wrap_operand.h>
 
 namespace sqlpp
 {
-	namespace vendor
-	{
-		template<typename T>
-			using value_type_t = typename wrap_operand<T>::type::_value_type;
-	}
+	template<typename T>
+		using value_type_t = value_type_of<wrap_operand_t<T>>;
 }
 #endif

include/sqlpp11/vendor/assignment.h

@@ -1,164 +0,0 @@
-/*
- * Copyright (c) 2013-2014, Roland Bock
- * All rights reserved.
- * 
- * Redistribution and use in source and binary forms, with or without modification,
- * are permitted provided that the following conditions are met:
- * 
- *   Redistributions of source code must retain the above copyright notice, this
- *   list of conditions and the following disclaimer.
- * 
- *   Redistributions in binary form must reproduce the above copyright notice, this
- *   list of conditions and the following disclaimer in the documentation and/or
- *   other materials provided with the distribution.
- * 
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
- * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
- * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
- * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR
- * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
- * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
- * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
- * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
- * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- */
-
-#ifndef SQLPP_ASSIGNMENT_H
-#define SQLPP_ASSIGNMENT_H
-
-#include <sqlpp11/default_value.h>
-#include <sqlpp11/null.h>
-#include <sqlpp11/tvin.h>
-#include <sqlpp11/serialize.h>
-#include <sqlpp11/vendor/serializer.h>
-#include <sqlpp11/vendor/simple_column.h>
-
-namespace sqlpp
-{
-	namespace vendor
-	{
-		template<typename T, typename Enable = void>
-		struct is_trivial_t
-		{
-			static constexpr bool _(const T&)
-			{
-				return false;
-			}
-		};
-
-		template<typename T>
-		struct is_trivial_t<T, typename std::enable_if<std::is_member_function_pointer<decltype(&T::_is_trivial)>::value, void>::type>
-		{
-			static bool _(const T& t)
-			{
-				return t._is_trivial();
-			}
-		};
-
-		template<typename T>
-		bool is_trivial(const T& t)
-		{
-			return is_trivial_t<typename T::value_type>::_(t);
-		}
-
-		template<typename Lhs, typename Rhs>
-			struct assignment_t
-			{
-				using _is_assignment = std::true_type;
-				using _column_t = Lhs;
-				using value_type = Rhs;
-				using _parameter_tuple_t = std::tuple<_column_t, Rhs>;
-				using _table_set = typename ::sqlpp::detail::make_joined_set<typename Lhs::_table_set, typename Rhs::_table_set>::type;
-
-				static_assert(can_be_null_t<_column_t>::value ? true : not std::is_same<Rhs, null_t>::value, "column must not be null");
-
-				assignment_t(_column_t lhs, value_type rhs):
-					_lhs(lhs), 
-					_rhs(rhs)
-				{}
-
-				assignment_t(const assignment_t&) = default;
-				assignment_t(assignment_t&&) = default;
-				assignment_t& operator=(const assignment_t&) = default;
-				assignment_t& operator=(assignment_t&&) = default;
-				~assignment_t() = default;
-
-				_column_t _lhs;
-				value_type _rhs;
-			};
-
-		template<typename Context, typename Lhs, typename Rhs>
-			struct serializer_t<Context, assignment_t<Lhs, Rhs>>
-			{
-				using T = assignment_t<Lhs, Rhs>;
-
-				static Context& _(const T& t, Context& context)
-				{
-					if ((trivial_value_is_null_t<typename T::_column_t>::value
-								and is_trivial_t<typename T::value_type>::_(t._rhs))
-							or (std::is_same<Rhs, null_t>::value))
-					{
-						serialize(simple_column(t._lhs), context);
-						context << "=NULL";
-					}
-					else
-					{
-						serialize(simple_column(t._lhs), context);
-						context << "=";
-						serialize(t._rhs, context);
-					}
-					return context;
-				}
-			};
-
-		template<typename Lhs, typename Rhs>
-			struct assignment_t<Lhs, tvin_t<Rhs>>
-			{
-				using _is_assignment = std::true_type;
-				using _column_t = Lhs;
-				using value_type = tvin_t<Rhs>;
-				using _parameter_tuple_t = std::tuple<_column_t, Rhs>;
-				using _table_set = typename ::sqlpp::detail::make_joined_set<typename Lhs::_table_set, typename Rhs::_table_set>::type;
-
-				static_assert(can_be_null_t<_column_t>::value, "column cannot be null");
-
-				assignment_t(_column_t lhs, value_type rhs):
-					_lhs(lhs), 
-					_rhs(rhs)
-				{}
-
-				assignment_t(const assignment_t&) = default;
-				assignment_t(assignment_t&&) = default;
-				assignment_t& operator=(const assignment_t&) = default;
-				assignment_t& operator=(assignment_t&&) = default;
-				~assignment_t() = default;
-
-				_column_t _lhs;
-				value_type _rhs;
-			};
-
-		template<typename Context, typename Lhs, typename Rhs>
-			struct serializer_t<Context, assignment_t<Lhs, tvin_t<Rhs>>>
-			{
-				using T = assignment_t<Lhs, tvin_t<Rhs>>;
-
-				static Context& _(const T& t, Context& context)
-				{
-					serialize(simple_column(t._lhs), context);
-					if (t._rhs._value._is_trivial())
-					{
-						context << "=NULL";
-					}
-					else
-					{
-						context << "=";
-						serialize(t._rhs._value, context);
-					}
-					return context;
-				}
-			};
-	}
-}
-
-#endif

include/sqlpp11/vendor/expression.h

@@ -1,244 +0,0 @@
-/*
- * Copyright (c) 2013-2014, Roland Bock
- * All rights reserved.
- * 
- * Redistribution and use in source and binary forms, with or without modification,
- * are permitted provided that the following conditions are met:
- * 
- *   Redistributions of source code must retain the above copyright notice, this
- *   list of conditions and the following disclaimer.
- * 
- *   Redistributions in binary form must reproduce the above copyright notice, this
- *   list of conditions and the following disclaimer in the documentation and/or
- *   other materials provided with the distribution.
- * 
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
- * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
- * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
- * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR
- * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
- * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
- * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
- * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
- * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- */
-
-#ifndef SQLPP_EXPRESSION_H
-#define SQLPP_EXPRESSION_H
-
-#include <sqlpp11/alias.h>
-#include <sqlpp11/boolean.h>
-#include <sqlpp11/tvin.h>
-#include <sqlpp11/vendor/noop.h>
-#include <sqlpp11/vendor/expression_fwd.h>
-#include <sqlpp11/vendor/serializer.h>
-#include <sqlpp11/vendor/wrap_operand.h>
-
-namespace sqlpp
-{
-	namespace vendor
-	{
-		template<typename Lhs, typename Rhs>
-			struct binary_expression_t<Lhs, tag::equal_to, Rhs>: public ::sqlpp::detail::boolean::template expression_operators<equal_to_t<Lhs, Rhs>>
-		{
-			using _value_type = ::sqlpp::detail::boolean;
-			using _parameter_tuple_t = std::tuple<Lhs, Rhs>;
-			using _table_set = typename ::sqlpp::detail::make_joined_set<typename Lhs::_table_set, typename Rhs::_table_set>::type;
-
-			binary_expression_t(Lhs lhs, Rhs rhs):
-				_lhs(lhs), 
-				_rhs(rhs)
-			{}
-
-			binary_expression_t(const binary_expression_t&) = default;
-			binary_expression_t(binary_expression_t&&) = default;
-			binary_expression_t& operator=(const binary_expression_t&) = default;
-			binary_expression_t& operator=(binary_expression_t&&) = default;
-			~binary_expression_t() = default;
-
-			Lhs _lhs;
-			maybe_tvin_t<Rhs> _rhs;
-		};
-
-		template<typename Context, typename Lhs, typename Rhs>
-			struct serializer_t<Context, equal_to_t<Lhs, Rhs>>
-			{
-				using T = equal_to_t<Lhs, Rhs>;
-
-				static Context& _(const T& t, Context& context)
-				{
-					context << "(";
-					serialize(t._lhs, context);
-					if (t._rhs._is_trivial())
-					{
-						context << " IS NULL";
-					}
-					else
-					{
-						context << "=";
-						serialize(t._rhs, context);
-					}
-					context << ")";
-					return context;
-				}
-			};
-
-		template<typename Lhs, typename Rhs>
-			struct binary_expression_t<Lhs, tag::not_equal_to, Rhs>: public ::sqlpp::detail::boolean::template expression_operators<not_equal_to_t<Lhs, Rhs>>
-		{
-			using _value_type = ::sqlpp::detail::boolean;
-			using _parameter_tuple_t = std::tuple<Lhs, Rhs>;
-			using _table_set = typename ::sqlpp::detail::make_joined_set<typename Lhs::_table_set, typename Rhs::_table_set>::type;
-
-			binary_expression_t(Lhs lhs, Rhs rhs):
-				_lhs(lhs), 
-				_rhs(rhs)
-			{}
-
-			binary_expression_t(const binary_expression_t&) = default;
-			binary_expression_t(binary_expression_t&&) = default;
-			binary_expression_t& operator=(const binary_expression_t&) = default;
-			binary_expression_t& operator=(binary_expression_t&&) = default;
-			~binary_expression_t() = default;
-
-			Lhs _lhs;
-			maybe_tvin_t<Rhs> _rhs;
-		};
-
-		template<typename Context, typename Lhs, typename Rhs>
-			struct serializer_t<Context, not_equal_to_t<Lhs, Rhs>>
-			{
-				using T = not_equal_to_t<Lhs, Rhs>;
-
-				static Context& _(const T& t, Context& context)
-				{
-					context << "(";
-					serialize(t._lhs, context);
-					if (t._rhs._is_trivial())
-					{
-						context << " IS NOT NULL";
-					}
-					else
-					{
-						context << "!=";
-						serialize(t._rhs, context);
-					}
-					context << ")";
-					return context;
-				}
-			};
-
-		template<typename Rhs>
-			struct unary_expression_t<tag::logical_not, Rhs>: public ::sqlpp::detail::boolean::template expression_operators<logical_not_t<Rhs>>
-		{
-			using _value_type = ::sqlpp::detail::boolean;
-			using _parameter_tuple_t = std::tuple<Rhs>;
-			using _table_set = typename Rhs::_table_set;
-
-			unary_expression_t(Rhs rhs):
-				_rhs(rhs)
-			{}
-
-			unary_expression_t(const unary_expression_t&) = default;
-			unary_expression_t(unary_expression_t&&) = default;
-			unary_expression_t& operator=(const unary_expression_t&) = default;
-			unary_expression_t& operator=(unary_expression_t&&) = default;
-			~unary_expression_t() = default;
-
-			Rhs _rhs;
-		};
-
-		template<typename Context, typename Rhs>
-			struct serializer_t<Context, logical_not_t<Rhs>>
-			{
-				using T = logical_not_t<Rhs>;
-
-				static Context& _(const T& t, Context& context)
-				{
-					context << "(";
-					context << "NOT ";
-					serialize(t._lhs, context);
-					context << ")";
-					return context;
-				}
-			};
-
-		template<typename Lhs, typename O, typename Rhs>
-			struct binary_expression_t: public O::_value_type::template expression_operators<binary_expression_t<Lhs, O, Rhs>>
-		{
-			using _lhs_t = Lhs;
-			using _rhs_t = Rhs;
-			using _value_type = typename O::_value_type;
-			using _parameter_tuple_t = std::tuple<_lhs_t, _rhs_t>;
-			using _table_set = typename ::sqlpp::detail::make_joined_set<typename Lhs::_table_set, typename Rhs::_table_set>::type;
-
-			binary_expression_t(_lhs_t lhs, _rhs_t rhs):
-				_lhs(lhs), 
-				_rhs(rhs)
-			{}
-
-			binary_expression_t(const binary_expression_t&) = default;
-			binary_expression_t(binary_expression_t&&) = default;
-			binary_expression_t& operator=(const binary_expression_t&) = default;
-			binary_expression_t& operator=(binary_expression_t&&) = default;
-			~binary_expression_t() = default;
-
-			_lhs_t _lhs;
-			_rhs_t _rhs;
-		};
-
-		template<typename Context, typename Lhs, typename O, typename Rhs>
-			struct serializer_t<Context, binary_expression_t<Lhs, O, Rhs>>
-			{
-				using T = binary_expression_t<Lhs, O, Rhs>;
-
-				static Context& _(const T& t, Context& context)
-				{
-					context << "(";
-					serialize(t._lhs, context);
-					context << O::_name;
-					serialize(t._rhs, context);
-					context << ")";
-					return context;
-				}
-			};
-
-		template<typename O, typename Rhs>
-			struct unary_expression_t: public O::_value_type::template expression_operators<unary_expression_t<O, Rhs>>
-		{
-			using _value_type = typename O::_value_type;
-			using _parameter_tuple_t = std::tuple<Rhs>;
-			using _table_set = typename Rhs::_table_set;
-
-			unary_expression_t(Rhs rhs):
-				_rhs(rhs)
-			{}
-
-			unary_expression_t(const unary_expression_t&) = default;
-			unary_expression_t(unary_expression_t&&) = default;
-			unary_expression_t& operator=(const unary_expression_t&) = default;
-			unary_expression_t& operator=(unary_expression_t&&) = default;
-			~unary_expression_t() = default;
-
-			Rhs _rhs;
-		};
-
-		template<typename Context, typename O, typename Rhs>
-			struct serializer_t<Context, unary_expression_t<O, Rhs>>
-			{
-				using T = unary_expression_t<O, Rhs>;
-
-				static Context& _(const T& t, Context& context)
-				{
-					context << "(";
-					context << O::_name;
-					serialize(t._rhs, context);
-					context << ")";
-					return context;
-				}
-			};
-	}
-}
-
-#endif

include/sqlpp11/vendor/expression_fwd.h

@@ -1,192 +0,0 @@
-/*
- * Copyright (c) 2013-2014, Roland Bock
- * All rights reserved.
- * 
- * Redistribution and use in source and binary forms, with or without modification,
- * are permitted provided that the following conditions are met:
- * 
- *   Redistributions of source code must retain the above copyright notice, this
- *   list of conditions and the following disclaimer.
- * 
- *   Redistributions in binary form must reproduce the above copyright notice, this
- *   list of conditions and the following disclaimer in the documentation and/or
- *   other materials provided with the distribution.
- * 
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
- * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
- * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
- * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR
- * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
- * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
- * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
- * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
- * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- */
-
-#ifndef SQLPP_EXPRESSION_FWD_H
-#define SQLPP_EXPRESSION_FWD_H
-
-namespace sqlpp
-{
-	namespace vendor
-	{
-		namespace tag
-		{
-			struct less
-			{
-				using _value_type = ::sqlpp::detail::boolean;
-				static constexpr const char* _name = "<";
-			};
-
-			struct less_equal
-			{
-				using _value_type = ::sqlpp::detail::boolean;
-				static constexpr const char* _name = "<=";
-			};
-
-			struct equal_to
-			{
-				using _value_type = ::sqlpp::detail::boolean;
-			};
-
-			struct not_equal_to
-			{
-				using _value_type = ::sqlpp::detail::boolean;
-			};
-
-			struct greater_equal
-			{
-				using _value_type = ::sqlpp::detail::boolean;
-				static constexpr const char* _name = ">=";
-			};
-
-			struct greater
-			{
-				using _value_type = ::sqlpp::detail::boolean;
-				static constexpr const char* _name = ">";
-			};
-
-			struct logical_or
-			{
-				using _value_type = ::sqlpp::detail::boolean;
-				static constexpr const char* _name = " OR ";
-			};
-
-			struct logical_and
-			{
-				using _value_type = ::sqlpp::detail::boolean;
-				static constexpr const char* _name = " AND ";
-			};
-
-			struct logical_not
-			{
-				using _value_type = ::sqlpp::detail::boolean;
-			};
-
-			template<typename ValueType>
-			struct plus
-			{
-				using _value_type = ValueType;
-				static constexpr const char* _name = "+";
-			};
-
-			template<typename ValueType>
-			struct minus
-			{
-				using _value_type = ValueType;
-				static constexpr const char* _name = "-";
-			};
-
-			template<typename ValueType>
-			struct multiplies
-			{
-				using _value_type = ValueType;
-				static constexpr const char* _name = "*";
-			};
-
-			struct divides
-			{
-				using _value_type = ::sqlpp::detail::floating_point;
-				static constexpr const char* _name = "/";
-			};
-
-			struct modulus
-			{
-				using _value_type = ::sqlpp::detail::integral;
-				static constexpr const char* _name = "%";
-			};
-
-			template<typename ValueType>
-			struct unary_minus
-			{
-				using _value_type = ValueType;
-				static constexpr const char* _name = "-";
-			};
-
-			template<typename ValueType>
-			struct unary_plus
-			{
-				using _value_type = ValueType;
-				static constexpr const char* _name = "+";
-			};
-		}
-
-		template<typename Lhs, typename O, typename Rhs>
-			struct binary_expression_t;
-
-		template<typename O, typename Rhs>
-			struct unary_expression_t;
-
-		template<typename Lhs, typename Rhs>
-			using less_than_t = binary_expression_t<Lhs, tag::less, Rhs>;
-
-		template<typename Lhs, typename Rhs>
-			using less_equal_t = binary_expression_t<Lhs, tag::less_equal, Rhs>;
-
-		template<typename Lhs, typename Rhs>
-			using equal_to_t = binary_expression_t<Lhs, tag::equal_to, Rhs>;
-
-		template<typename Lhs, typename Rhs>
-			using not_equal_to_t = binary_expression_t<Lhs, tag::not_equal_to, Rhs>;
-
-		template<typename Lhs, typename Rhs>
-			using greater_than_t = binary_expression_t<Lhs, tag::greater, Rhs>;
-
-		template<typename Lhs, typename Rhs>
-			using greater_equal_t = binary_expression_t<Lhs, tag::greater_equal, Rhs>;
-
-		template<typename Lhs, typename Rhs>
-			using logical_and_t = binary_expression_t<Lhs, tag::logical_and, Rhs>;
-
-		template<typename Lhs, typename Rhs>
-			using logical_or_t = binary_expression_t<Lhs, tag::logical_or, Rhs>;
-
-		template<typename Lhs, typename ValueType, typename Rhs>
-			using plus_t = binary_expression_t<Lhs, tag::plus<ValueType>, Rhs>;
-
-		template<typename Lhs, typename ValueType, typename Rhs>
-			using minus_t = binary_expression_t<Lhs, tag::minus<ValueType>, Rhs>;
-
-		template<typename Lhs, typename ValueType, typename Rhs>
-			using multiplies_t = binary_expression_t<Lhs, tag::multiplies<ValueType>, Rhs>;
-
-		template<typename Lhs, typename Rhs>
-			using divides_t = binary_expression_t<Lhs, tag::divides, Rhs>;
-
-		template<typename Lhs, typename Rhs>
-			using modulus_t = binary_expression_t<Lhs, tag::modulus, Rhs>;
-
-		template<typename Rhs>
-			using logical_not_t = unary_expression_t<tag::logical_not, Rhs>;
-
-		template<typename ValueType, typename Rhs>
-			using unary_plus_t = unary_expression_t<tag::unary_plus<ValueType>, Rhs>;
-
-		template<typename ValueType, typename Rhs>
-			using unary_minus_t = unary_expression_t<tag::unary_minus<ValueType>, Rhs>;
-
-	}
-}
-
-#endif

include/sqlpp11/vendor/extra_tables.h

@@ -1,114 +0,0 @@
-/*
- * Copyright (c) 2013-2014, Roland Bock
- * All rights reserved.
- * 
- * Redistribution and use in source and binary forms, with or without modification,
- * are permitted provided that the following conditions are met:
- * 
- *   Redistributions of source code must retain the above copyright notice, this
- *   list of conditions and the following disclaimer.
- * 
- *   Redistributions in binary form must reproduce the above copyright notice, this
- *   list of conditions and the following disclaimer in the documentation and/or
- *   other materials provided with the distribution.
- * 
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
- * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
- * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
- * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR
- * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
- * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
- * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
- * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
- * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- */
-
-#ifndef SQLPP_EXTRA_TABLES_H
-#define SQLPP_EXTRA_TABLES_H
-
-#include <sqlpp11/type_traits.h>
-#include <sqlpp11/detail/logic.h>
-#include <sqlpp11/vendor/policy_update.h>
-
-namespace sqlpp
-{
-	namespace vendor
-	{
-		// EXTRA_TABLES
-		template<typename... Tables>
-			struct extra_tables_t
-			{
-				using _is_extra_tables = std::true_type;
-
-				static_assert(sizeof...(Tables), "at least one table or join argument required in extra_tables()");
-
-				static_assert(not ::sqlpp::detail::has_duplicates<Tables...>::value, "at least one duplicate argument detected in extra_tables()");
-
-				static_assert(::sqlpp::detail::all_t<is_table_t<Tables>::value...>::value, "at least one argument is not a table or join in extra_tables()");
-
-				using _table_set = ::sqlpp::detail::make_joined_set_t<typename Tables::_table_set...>;
-
-
-				extra_tables_t()
-				{}
-
-				extra_tables_t(const extra_tables_t&) = default;
-				extra_tables_t(extra_tables_t&&) = default;
-				extra_tables_t& operator=(const extra_tables_t&) = default;
-				extra_tables_t& operator=(extra_tables_t&&) = default;
-				~extra_tables_t() = default;
-
-				template<typename Policies>
-					struct _methods_t
-					{
-					};
-			};
-
-		struct no_extra_tables_t
-		{
-			using _is_noop = std::true_type;
-			using _table_set = ::sqlpp::detail::type_set<>;
-
-			template<typename Policies>
-				struct _methods_t
-				{
-					template<typename T>
-					using _new_statement_t = typename Policies::template _new_statement_t<no_extra_tables_t, T>;
-
-					template<typename... Args>
-						auto extra_tables(Args...)
-						-> _new_statement_t<extra_tables_t<Args...>>
-						{
-							return { *static_cast<typename Policies::_statement_t*>(this), extra_tables_t<Args...>{} };
-						}
-				};
-		};
-
-		// Interpreters
-		template<typename Context, typename Database, typename... Tables>
-			struct serializer_t<Context, extra_tables_t<Database, Tables...>>
-			{
-				using T = extra_tables_t<Database, Tables...>;
-
-				static Context& _(const T& t, Context& context)
-				{
-					return context;
-				}
-			};
-
-		template<typename Context>
-			struct serializer_t<Context, no_extra_tables_t>
-			{
-				using T = no_extra_tables_t;
-
-				static Context& _(const T& t, Context& context)
-				{
-					return context;
-				}
-			};
-
-	}
-}
-
-#endif

include/sqlpp11/vendor/from.h

@@ -1,158 +0,0 @@
-/*
- * Copyright (c) 2013-2014, Roland Bock
- * All rights reserved.
- * 
- * Redistribution and use in source and binary forms, with or without modification,
- * are permitted provided that the following conditions are met:
- * 
- *   Redistributions of source code must retain the above copyright notice, this
- *   list of conditions and the following disclaimer.
- * 
- *   Redistributions in binary form must reproduce the above copyright notice, this
- *   list of conditions and the following disclaimer in the documentation and/or
- *   other materials provided with the distribution.
- * 
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
- * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
- * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
- * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR
- * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
- * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
- * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
- * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
- * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- */
-
-#ifndef SQLPP_FROM_H
-#define SQLPP_FROM_H
-
-#include <sqlpp11/type_traits.h>
-#include <sqlpp11/vendor/interpretable_list.h>
-#include <sqlpp11/vendor/interpret_tuple.h>
-#include <sqlpp11/detail/logic.h>
-#include <sqlpp11/vendor/policy_update.h>
-
-namespace sqlpp
-{
-	namespace vendor
-	{
-		// FROM
-		template<typename Database, typename... Tables>
-			struct from_t
-			{
-				using _is_from = std::true_type;
-				using _is_dynamic = typename std::conditional<std::is_same<Database, void>::value, std::false_type, std::true_type>::type;
-
-				static_assert(_is_dynamic::value or sizeof...(Tables), "at least one table or join argument required in from()");
-
-				// FIXME: Joins contain two tables. This is not being dealt with at the moment when looking at duplicates, for instance
-				static_assert(not ::sqlpp::detail::has_duplicates<Tables...>::value, "at least one duplicate argument detected in from()");
-
-				static_assert(::sqlpp::detail::all_t<is_table_t<Tables>::value...>::value, "at least one argument is not a table or join in from()");
-
-				using _table_set = ::sqlpp::detail::make_joined_set_t<typename Tables::_table_set...>;
-
-
-				from_t(Tables... tables):
-					_tables(tables...)
-				{}
-
-				from_t(const from_t&) = default;
-				from_t(from_t&&) = default;
-				from_t& operator=(const from_t&) = default;
-				from_t& operator=(from_t&&) = default;
-				~from_t() = default;
-
-				template<typename Policies>
-					struct _methods_t
-					{
-						template<typename Table>
-							void add_from(Table table)
-							{
-								static_assert(_is_dynamic::value, "add_from must not be called for static from()");
-								static_assert(is_table_t<Table>::value, "invalid table argument in add_from()");
-
-								using ok = ::sqlpp::detail::all_t<_is_dynamic::value, is_table_t<Table>::value>;
-
-								_add_from_impl(table, ok()); // dispatch to prevent compile messages after the static_assert
-							}
-
-					private:
-						template<typename Table>
-							void _add_from_impl(Table table, const std::true_type&)
-							{
-								return static_cast<typename Policies::_statement_t*>(this)->_from._dynamic_tables.emplace_back(table);
-							}
-
-						template<typename Table>
-							void _add_from_impl(Table table, const std::false_type&);
-					};
-
-				std::tuple<Tables...> _tables;
-				vendor::interpretable_list_t<Database> _dynamic_tables;
-			};
-
-		struct no_from_t
-		{
-			using _is_noop = std::true_type;
-			using _table_set = ::sqlpp::detail::type_set<>;
-
-			template<typename Policies>
-				struct _methods_t
-				{
-					using _database_t = typename Policies::_database_t;
-					template<typename T>
-					using _new_statement_t = typename Policies::template _new_statement_t<no_from_t, T>;
-
-					template<typename... Args>
-						auto from(Args... args)
-						-> _new_statement_t<from_t<void, Args...>>
-						{
-							return { *static_cast<typename Policies::_statement_t*>(this), from_t<void, Args...>{args...} };
-						}
-
-					template<typename... Args>
-						auto dynamic_from(Args... args)
-						-> _new_statement_t<from_t<_database_t, Args...>>
-						{
-							static_assert(not std::is_same<_database_t, void>::value, "dynamic_from must not be called in a static statement");
-							return { *static_cast<typename Policies::_statement_t*>(this), vendor::from_t<_database_t, Args...>{args...} };
-						}
-				};
-		};
-
-		// Interpreters
-		template<typename Context, typename Database, typename... Tables>
-			struct serializer_t<Context, from_t<Database, Tables...>>
-			{
-				using T = from_t<Database, Tables...>;
-
-				static Context& _(const T& t, Context& context)
-				{
-					if (sizeof...(Tables) == 0 and t._dynamic_tables.empty())
-						return context;
-					context << " FROM ";
-					interpret_tuple(t._tables, ',', context);
-					if (sizeof...(Tables) and not t._dynamic_tables.empty())
-						context << ',';
-					interpret_list(t._dynamic_tables, ',', context);
-					return context;
-				}
-			};
-
-		template<typename Context>
-			struct serializer_t<Context, no_from_t>
-			{
-				using T = no_from_t;
-
-				static Context& _(const T& t, Context& context)
-				{
-					return context;
-				}
-			};
-
-	}
-}
-
-#endif

include/sqlpp11/vendor/group_by.h

@@ -1,168 +0,0 @@
-/*
- * Copyright (c) 2013-2014, Roland Bock
- * All rights reserved.
- * 
- * Redistribution and use in source and binary forms, with or without modification,
- * are permitted provided that the following conditions are met:
- * 
- *   Redistributions of source code must retain the above copyright notice, this
- *   list of conditions and the following disclaimer.
- * 
- *   Redistributions in binary form must reproduce the above copyright notice, this
- *   list of conditions and the following disclaimer in the documentation and/or
- *   other materials provided with the distribution.
- * 
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
- * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
- * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
- * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR
- * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
- * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
- * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
- * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
- * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- */
-
-#ifndef SQLPP_GROUP_BY_H
-#define SQLPP_GROUP_BY_H
-
-#include <tuple>
-#include <sqlpp11/type_traits.h>
-#include <sqlpp11/vendor/expression.h>
-#include <sqlpp11/vendor/interpret_tuple.h>
-#include <sqlpp11/vendor/interpretable_list.h>
-#include <sqlpp11/vendor/policy_update.h>
-#include <sqlpp11/detail/logic.h>
-
-namespace sqlpp
-{
-	namespace vendor
-	{
-		// GROUP BY
-		template<typename Database, typename... Expressions>
-			struct group_by_t
-			{
-				using _is_group_by = std::true_type;
-				using _is_dynamic = typename std::conditional<std::is_same<Database, void>::value, std::false_type, std::true_type>::type;
-				using _parameter_tuple_t = std::tuple<Expressions...>;
-				using _parameter_list_t = typename make_parameter_list_t<_parameter_tuple_t>::type;
-
-				using _table_set = typename ::sqlpp::detail::make_joined_set<typename Expressions::_table_set...>::type;
-
-				static_assert(_is_dynamic::value or sizeof...(Expressions), "at least one expression (e.g. a column) required in group_by()");
-
-				static_assert(not ::sqlpp::detail::has_duplicates<Expressions...>::value, "at least one duplicate argument detected in group_by()");
-
-				static_assert(::sqlpp::detail::all_t<is_expression_t<Expressions>::value...>::value, "at least one argument is not an expression in group_by()");
-
-				group_by_t(Expressions... expressions):
-					_expressions(expressions...)
-				{}
-
-				group_by_t(const group_by_t&) = default;
-				group_by_t(group_by_t&&) = default;
-				group_by_t& operator=(const group_by_t&) = default;
-				group_by_t& operator=(group_by_t&&) = default;
-				~group_by_t() = default;
-
-				template<typename Policies>
-					struct _methods_t
-					{
-						template<typename Expression>
-							void add_group_by_ntc(Expression expression)
-							{
-								add_group_by<Expression, std::false_type>(expression);
-							}
-
-						template<typename Expression, typename TableCheckRequired = std::true_type>
-							void add_group_by(Expression expression)
-							{
-								static_assert(_is_dynamic::value, "add_group_by must not be called for static group_by");
-								static_assert(is_expression_t<Expression>::value, "invalid expression argument in add_group_by()");
-								static_assert(TableCheckRequired::value or Policies::template _no_unknown_tables<Expression>::value, "expression uses tables unknown to this statement in add_group_by()");
-
-								using ok = ::sqlpp::detail::all_t<_is_dynamic::value, is_expression_t<Expression>::value>;
-
-								_add_group_by_impl(expression, ok()); // dispatch to prevent compile messages after the static_assert
-							}
-
-					private:
-						template<typename Expression>
-							void _add_group_by_impl(Expression expression, const std::true_type&)
-							{
-								return static_cast<typename Policies::_statement_t*>(this)->_group_by._dynamic_expressions.emplace_back(expression);
-							}
-
-						template<typename Expression>
-							void _add_group_by_impl(Expression expression, const std::false_type&);
-					};
-
-				const group_by_t& _group_by() const { return *this; }
-				_parameter_tuple_t _expressions;
-				vendor::interpretable_list_t<Database> _dynamic_expressions;
-			};
-
-		struct no_group_by_t
-		{
-			using _is_noop = std::true_type;
-			using _table_set = ::sqlpp::detail::type_set<>;
-
-			template<typename Policies>
-				struct _methods_t
-				{
-					using _database_t = typename Policies::_database_t;
-					template<typename T>
-					using _new_statement_t = typename Policies::template _new_statement_t<no_group_by_t, T>;
-
-					template<typename... Args>
-						auto group_by(Args... args)
-						-> _new_statement_t<group_by_t<void, Args...>>
-						{
-							return { *static_cast<typename Policies::_statement_t*>(this), group_by_t<void, Args...>{args...} };
-						}
-
-					template<typename... Args>
-						auto dynamic_group_by(Args... args)
-						-> _new_statement_t<group_by_t<_database_t, Args...>>
-						{
-							static_assert(not std::is_same<_database_t, void>::value, "dynamic_group_by must not be called in a static statement");
-							return { *static_cast<typename Policies::_statement_t*>(this), vendor::group_by_t<_database_t, Args...>{args...} };
-						}
-				};
-		};
-
-		// Interpreters
-		template<typename Context, typename Database, typename... Expressions>
-			struct serializer_t<Context, group_by_t<Database, Expressions...>>
-			{
-				using T = group_by_t<Database, Expressions...>;
-
-				static Context& _(const T& t, Context& context)
-				{
-					if (sizeof...(Expressions) == 0 and t._dynamic_expressions.empty())
-						return context;
-					context << " GROUP BY ";
-					interpret_tuple(t._expressions, ',', context);
-					if (sizeof...(Expressions) and not t._dynamic_expressions.empty())
-						context << ',';
-					interpret_list(t._dynamic_expressions, ',', context);
-					return context;
-				}
-			};
-
-		template<typename Context>
-			struct serializer_t<Context, no_group_by_t>
-			{
-				using T = no_group_by_t;
-
-				static Context& _(const T& t, Context& context)
-				{
-					return context;
-				}
-			};
-
-	}
-}
-
-#endif

include/sqlpp11/vendor/having.h

@@ -1,164 +0,0 @@
-/*
- * Copyright (c) 2013-2014, Roland Bock
- * All rights reserved.
- * 
- * Redistribution and use in source and binary forms, with or without modification,
- * are permitted provided that the following conditions are met:
- * 
- *   Redistributions of source code must retain the above copyright notice, this
- *   list of conditions and the following disclaimer.
- * 
- *   Redistributions in binary form must reproduce the above copyright notice, this
- *   list of conditions and the following disclaimer in the documentation and/or
- *   other materials provided with the distribution.
- * 
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
- * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
- * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
- * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR
- * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
- * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
- * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
- * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
- * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- */
-
-#ifndef SQLPP_HAVING_H
-#define SQLPP_HAVING_H
-
-#include <sqlpp11/type_traits.h>
-#include <sqlpp11/vendor/expression.h>
-#include <sqlpp11/vendor/interpret_tuple.h>
-#include <sqlpp11/vendor/interpretable_list.h>
-#include <sqlpp11/vendor/policy_update.h>
-#include <sqlpp11/detail/logic.h>
-
-namespace sqlpp
-{
-	namespace vendor
-	{
-		// HAVING
-		template<typename Database, typename... Expressions>
-			struct having_t
-			{
-				using _is_having = std::true_type;
-				using _is_dynamic = typename std::conditional<std::is_same<Database, void>::value, std::false_type, std::true_type>::type;
-				using _parameter_tuple_t = std::tuple<Expressions...>;
-
-				static_assert(_is_dynamic::value or sizeof...(Expressions), "at least one expression argument required in having()");
-				static_assert(::sqlpp::detail::all_t<is_expression_t<Expressions>::value...>::value, "at least one argument is not an expression in having()");
-
-				using _parameter_list_t = typename make_parameter_list_t<_parameter_tuple_t>::type;
-
-				using _table_set = typename ::sqlpp::detail::make_joined_set<typename Expressions::_table_set...>::type;
-
-				having_t(Expressions... expressions):
-					_expressions(expressions...)
-				{}
-
-				having_t(const having_t&) = default;
-				having_t(having_t&&) = default;
-				having_t& operator=(const having_t&) = default;
-				having_t& operator=(having_t&&) = default;
-				~having_t() = default;
-
-				template<typename Policies>
-					struct _methods_t
-					{
-						template<typename Expression>
-							void add_having_ntc(Expression expression)
-							{
-								add_having<Expression, std::false_type>(expression);
-							}
-
-						template<typename Expression, typename TableCheckRequired = std::true_type>
-							void add_having(Expression expression)
-							{
-								static_assert(_is_dynamic::value, "add_having must not be called for static having");
-								static_assert(is_expression_t<Expression>::value, "invalid expression argument in add_having()");
-								static_assert(TableCheckRequired::value or Policies::template _no_unknown_tables<Expression>::value, "expression uses tables unknown to this statement in add_having()");
-
-								using ok = ::sqlpp::detail::all_t<_is_dynamic::value, is_expression_t<Expression>::value>;
-
-								_add_having_impl(expression, ok()); // dispatch to prevent compile messages after the static_assert
-							}
-
-					private:
-						template<typename Expression>
-							void _add_having_impl(Expression expression, const std::true_type&)
-							{
-								return static_cast<typename Policies::_statement_t*>(this)->_having._dynamic_expressions.emplace_back(expression);
-							}
-
-						template<typename Expression>
-							void _add_having_impl(Expression expression, const std::false_type&);
-					};
-
-				_parameter_tuple_t _expressions;
-				vendor::interpretable_list_t<Database> _dynamic_expressions;
-			};
-
-		struct no_having_t
-		{
-			using _is_noop = std::true_type;
-			using _table_set = ::sqlpp::detail::type_set<>;
-
-			template<typename Policies>
-				struct _methods_t
-				{
-					using _database_t = typename Policies::_database_t;
-					template<typename T>
-					using _new_statement_t = typename Policies::template _new_statement_t<no_having_t, T>;
-
-					template<typename... Args>
-						auto having(Args... args)
-						-> _new_statement_t<having_t<void, Args...>>
-						{
-							return { *static_cast<typename Policies::_statement_t*>(this), having_t<void, Args...>{args...} };
-						}
-
-					template<typename... Args>
-						auto dynamic_having(Args... args)
-						-> _new_statement_t<having_t<_database_t, Args...>>
-						{
-							static_assert(not std::is_same<_database_t, void>::value, "dynamic_having must not be called in a static statement");
-							return { *static_cast<typename Policies::_statement_t*>(this), vendor::having_t<_database_t, Args...>{args...} };
-						}
-				};
-		};
-
-		// Interpreters
-		template<typename Context, typename Database, typename... Expressions>
-			struct serializer_t<Context, having_t<Database, Expressions...>>
-			{
-				using T = having_t<Database, Expressions...>;
-
-				static Context& _(const T& t, Context& context)
-				{
-					if (sizeof...(Expressions) == 0 and t._dynamic_expressions.empty())
-						return context;
-					context << " HAVING ";
-					interpret_tuple(t._expressions, " AND ", context);
-					if (sizeof...(Expressions) and not t._dynamic_expressions.empty())
-						context << " AND ";
-					interpret_list(t._dynamic_expressions, " AND ", context);
-					return context;
-				}
-			};
-
-		template<typename Context>
-			struct serializer_t<Context, no_having_t>
-			{
-				using T = no_having_t;
-
-				static Context& _(const T& t, Context& context)
-				{
-					return context;
-				}
-			};
-
-	}
-}
-
-#endif

include/sqlpp11/vendor/insert_value.h

@@ -1,124 +0,0 @@
-/*
- * Copyright (c) 2013-2014, Roland Bock
- * All rights reserved.
- * 
- * Redistribution and use in source and binary forms, with or without modification,
- * are permitted provided that the following conditions are met:
- * 
- *   Redistributions of source code must retain the above copyright notice, this
- *   list of conditions and the following disclaimer.
- * 
- *   Redistributions in binary form must reproduce the above copyright notice, this
- *   list of conditions and the following disclaimer in the documentation and/or
- *   other materials provided with the distribution.
- * 
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
- * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
- * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
- * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR
- * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
- * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
- * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
- * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
- * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- */
-
-#ifndef SQLPP_INSERT_VALUE_H
-#define SQLPP_INSERT_VALUE_H
-
-#include <sqlpp11/default_value.h>
-#include <sqlpp11/null.h>
-#include <sqlpp11/tvin.h>
-#include <sqlpp11/type_traits.h>
-#include <sqlpp11/vendor/serializer.h>
-#include <sqlpp11/detail/type_set.h>
-
-namespace sqlpp
-{
-	namespace vendor
-	{
-		namespace detail
-		{
-			template<typename Type, bool>
-				struct type_if
-				{
-					using type = Type;
-					using _table_set = typename Type::_table_set;
-				};
-
-			template<typename Type>
-				struct type_if<Type, false>
-				{
-					struct type
-					{
-						using _table_set = sqlpp::detail::type_set<>;
-					};
-				};
-		}
-
-		template<typename Column>
-			struct insert_value_t
-			{
-				using _is_insert_value = std::true_type;
-				using _pure_value_t = typename Column::_value_type::_cpp_value_type;
-				using _wrapped_value_t = typename wrap_operand<_pure_value_t>::type;
-				using _tvin_t = typename detail::type_if<tvin_t<_wrapped_value_t>, can_be_null_t<Column>::value>::type; // static asserts and SFINAE do not work together
-				using _null_t = typename detail::type_if<null_t, can_be_null_t<Column>::value>::type; // static asserts and SFINAE do not work together
-
-				insert_value_t(assignment_t<Column, _wrapped_value_t> assignment):
-					_is_null(false),
-					_is_default(false),
-					_value(assignment._rhs)
-				{}
-
-				insert_value_t(assignment_t<Column, _tvin_t> assignment):
-					_is_null(assignment._rhs._is_trivial()),
-					_is_default(false),
-					_value(assignment._rhs._value)
-				{}
-
-				insert_value_t(const assignment_t<Column, _null_t>&):
-					_is_null(true),
-					_is_default(false),
-					_value()
-				{}
-
-				insert_value_t(const assignment_t<Column, ::sqlpp::default_value_t>&):
-					_is_null(false),
-					_is_default(true),
-					_value()
-				{}
-
-				insert_value_t(const insert_value_t&) = default;
-				insert_value_t(insert_value_t&&) = default;
-				insert_value_t& operator=(const insert_value_t&) = default;
-				insert_value_t& operator=(insert_value_t&&) = default;
-				~insert_value_t() = default;
-
-				bool _is_null;
-				bool _is_default;
-				_wrapped_value_t _value;
-			};
-
-		template<typename Context, typename ValueType>
-			struct serializer_t<Context, insert_value_t<ValueType>>
-			{
-				using T = insert_value_t<ValueType>;
-
-				static Context& _(const T& t, Context& context)
-				{
-					if (t._is_null)
-						context << "NULL";
-					else if (t._is_default)
-						context << "DEFAULT";
-					else
-						serialize(t._value, context);
-					return context;
-				}
-			};
-
-	}
-}
-
-#endif