diff --git a/connector_api/bind_result.h b/connector_api/bind_result.h
new file mode 100644
index 00000000..8999c357
--- /dev/null
+++ b/connector_api/bind_result.h
@@ -0,0 +1,91 @@
+/*
+ * Copyright (c) 2013, 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_DATABASE_BIND_RESULT_H
+#define SQLPP_DATABASE_BIND_RESULT_H
+
+#include <memory>
+
+namespace sqlpp
+{
+	namespace database
+	{
+		/*
+		 * bind_result_t binds values of a sqlpp11 result row
+		 * to the results of a statement
+		 */
+		class bind_result_t
+		{
+		public:
+			bind_result_t(); // default constructor for a result that will not yield a valid row
+			bind_result_t(...);
+			bind_result_t(const bind_result_t&) = delete;
+			bind_result_t(bind_result_t&& rhs);
+			bind_result_t& operator=(const bind_result_t&) = delete;
+			bind_result_t& operator=(bind_result_t&&);
+			~bind_result_t();
+
+			bool operator==(const bind_result_t& rhs) const;
+
+			template<typename ResultRow>
+			void next(ResultRow& result_row);
+
+			// something similar to this:
+			/*
+			{
+				if (!_handle)
+				{
+					result_row.invalidate();
+					return;
+				}
+
+				if (next_impl())
+				{
+					if (not result_row)
+					{
+						result_row.validate();
+					}
+					result_row._bind(*this); // bind result row values to results
+				}
+				else
+				{
+					if (result_row)
+						result_row.invalidate();
+				}
+			};
+			*/
+
+			// These are called by the result row to bind individual result values
+			void _bind_boolean_result(size_t index, signed char* value, bool* is_null);
+			void _bind_integral_result(size_t index, int64_t* value, bool* is_null);
+			void _bind_text_result(size_t index, const char** text, size_t* len);
+			...
+		};
+
+	}
+}
+#endif
diff --git a/connector_api/char_result.h b/connector_api/char_result.h
new file mode 100644
index 00000000..355ba959
--- /dev/null
+++ b/connector_api/char_result.h
@@ -0,0 +1,70 @@
+/*
+ * Copyright (c) 2013, 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_DATABASE_CHAR_RESULT_H
+#define SQLPP_DATABASE_CHAR_RESULT_H
+
+#include <sqlpp11/vendor/char_result_row.h>
+
+namespace sqlpp
+{
+	namespace database
+	{
+		/*
+		 * char_result_t yields results as 
+		 * sqlpp11::vendor::char_result_row_t
+		 */
+		class char_result_t
+		{
+			::sqlpp11::vendor::char_result_row_t char_result_row;
+		public:
+			char_result_t(); // default constructor for a result that will not yield a valid row
+			char_result_t(...);
+			char_result_t(const char_result_t&) = delete;
+			char_result_t(char_result_t&& rhs);
+			char_result_t& operator=(const char_result_t&) = delete;
+			char_result_t& operator=(char_result_t&&);
+			~char_result_t();
+
+			bool operator==(const char_result_t& rhs) const;
+
+			template<typename ResultRow>
+			void next(ResultRow& result_row);
+
+			// Something like
+			/*
+			{
+				next_impl();
+				if (_char_result_row.data)
+					result_row = _char_result_row;
+				else
+					result_row.invalidate();
+			};
+			*/
+	}
+}
+#endif
diff --git a/connector_api/connection.h b/connector_api/connection.h
new file mode 100644
index 00000000..d6e98663
--- /dev/null
+++ b/connector_api/connection.h
@@ -0,0 +1,140 @@
+/*
+ * Copyright (c) 2013, 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_DATABASE_CONNECTION_H
+#define SQLPP_DATABASE_CONNECTION_H
+
+#include <string>
+#include <sqlpp11/connection.h>
+#include <sqlpp11/database/char_result.h> // You may use char result or bind result or both
+#include <sqlpp11/database/bind_result.h> // to represent results of select and prepared select
+
+namespace sqlpp
+{
+	namespace database
+	{
+		// The context is not a requirement, but if the database requires 
+		// any deviations from the SQL standard, you should use your own 
+		// context in order to specialize the behaviour, see also interpreter.h
+		struct context_t
+		{
+			template<typename T>
+				std::ostream& operator<<(T t);
+
+			std::string escape(std::string arg);
+		};
+
+		class connection: public sqlpp::connection // this inheritance helps with ADL for dynamic_select, for instance
+		{
+		public:
+			using _prepared_statement_t = << handle to a prepared statement of the database >>;
+			using _context_t = << This context is used to interpret the dynamic parts of dynamic statemtents>>;
+
+			connection(...);
+			~connection();
+			connection(const connection&) = delete;
+			connection(connection&&) = delete;
+			connection& operator=(const connection&) = delete;
+			connection& operator=(connection&&) = delete;
+
+			//! "direct" select
+			template<typename Select>
+			<<char_result_t or bind_result_t>> select(const Select& s);
+
+			//! prepared select
+			template<typename Select>
+			_prepared_statement_t prepare_select(Select& s);
+
+			template<typename PreparedSelect>
+			<<char_result_t or bind_result_t>> run_prepared_select(const PreparedSelect& s); // call s._bind_params()
+
+			//! "direct insert
+			template<typename Insert>
+			size_t insert(const Insert& i);
+
+			//! prepared insert
+			template<typename Insert>
+			_prepared_statement_t prepare_insert(Insert& i);
+
+			template<typename PreparedInsert>
+			size_t run_prepared_insert(const PreparedInsert& i); // call i._bind_params()
+
+			//! "direct" update
+			template<typename Update>
+			size_t update(const Update& u);
+
+			//! "prepared" update
+			template<typename Update>
+			_prepared_statement_t prepare_update(Update& u);
+
+			template<typename PreparedUpdate>
+			size_t run_prepared_update(const PreparedUpdate& u); // call u._bind_params()
+
+			//! "direct" remove
+			template<typename Remove>
+			size_t remove(const Remove& r)
+
+			//! prepared remove
+			template<typename Remove>
+			_prepared_statement_t prepare_remove(Remove& r);
+
+			template<typename PreparedRemove>
+			size_t run_prepared_remove(const PreparedRemove& r); // call r._bind_params()
+
+			//! call run on the argument
+			template<typename T>
+				auto run(const T& t) -> decltype(t._run(*this))
+				{
+					return t._run(*this);
+				}
+
+			//! call prepare on the argument
+			template<typename T>
+				auto prepare(const T& t) -> decltype(t._prepare(*this))
+				{
+					return t._prepare(*this);
+				}
+
+			//! start transaction
+			void start_transaction();
+
+			//! commit transaction (or throw transaction if the transaction has been finished already)
+			void commit_transaction();
+
+			//! rollback transaction with or without reporting the rollback (or throw if the transaction has been finished already)
+			void rollback_transaction(bool report);
+
+			//! report a rollback failure (will be called by transactions in case of a rollback failure in the destructor)
+			void report_rollback_failure(const std::string message) noexcept;
+		};
+
+	}
+}
+
+#include <sqlpp11/database/interpreter.h>
+
+#endif
diff --git a/connector_api/interpreter.h b/connector_api/interpreter.h
new file mode 100644
index 00000000..9a83c008
--- /dev/null
+++ b/connector_api/interpreter.h
@@ -0,0 +1,62 @@
+/*
+ * Copyright (c) 2013, 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_DATABASE_INTERPRETER_H
+#define SQLPP_DATABASE_INTERPRETER_H
+
+#include <sqlpp11/vendor/concat.h>
+#include <sqlpp11/vendor/insert_list.h>
+
+/*
+ * sqlpp11 offers an interpreter that can be used to serialize the expression tree 
+ * into a standard SQL string.
+ *
+ * The connector library can specialize the interpreter template to partially or 
+ * completely change the way the expression tree is interpreted.
+ *
+ * For example, this specialization will produce indexed parameters instead of just '?'
+ */
+namespace sqlpp
+{
+	namespace vendor
+	{
+		template<typename ValueType, typename NameType>
+			struct interpreter_t<database::context_t, parameter_t<ValueType, NameType>>
+			{
+				using T = parameter_t<ValueType, NameType>;
+
+				static database::context_t& _(const T& t, database::context_t& context)
+				{
+					context << "?" << context.count();
+					context.pop_count();
+					return context;
+				}
+			};
+
+	}
+}
+
+#endif
diff --git a/connector_api/prepared_statement.h b/connector_api/prepared_statement.h
new file mode 100644
index 00000000..4a99ee03
--- /dev/null
+++ b/connector_api/prepared_statement.h
@@ -0,0 +1,58 @@
+/*
+ * Copyright (c) 2013, 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_DATABASE_PREPARED_STATEMENT_H
+#define SQLPP_DATABASE_PREPARED_STATEMENT_H
+
+#include <memory>
+#include <string>
+
+namespace sqlpp
+{
+	namespace database
+	{
+		class prepared_statement_t
+		{
+		public:
+			prepared_statement_t() = delete;
+			prepared_statement_t(...);
+			prepared_statement_t(const prepared_statement_t&) = delete;
+			prepared_statement_t(prepared_statement_t&& rhs);
+			prepared_statement_t& operator=(const prepared_statement_t&) = delete;
+			prepared_statement_t& operator=(prepared_statement_t&&);
+			~prepared_statement_t();
+
+			bool operator==(const prepared_statement_t& rhs) const;
+
+			// These are called by the sqlpp11::prepared_*_t to bind the individual parameters
+			void _bind_boolean_parameter(size_t index, const signed char* value, bool is_null);
+			void _bind_integral_parameter(size_t index, const int64_t* value, bool is_null);
+			void _bind_text_parameter(size_t index, const std::string* value, bool is_null);
+		};
+	}
+}
+#endif
diff --git a/database_api/api.h b/database_api/api.h
deleted file mode 100644
index e3519075..00000000
--- a/database_api/api.h
+++ /dev/null
@@ -1,137 +0,0 @@
-/*
- * Copyright (c) 2013, 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_DATABASE_API_H
-#define SQLPP_DATABASE_API_H
-
-#include <string>
-#include <sqlpp11/connection.h>
-#include <sqlpp11/raw_result_row.h>
-
-namespace sqlpp
-{
-	namespace connector_name
-	{
-		class result
-		{
-		public:
-			result() = default;
-			result(const result&) = delete;
-			result(result&& rhs) = default;
-			result& operator=(const result&) = delete;
-			result& operator=(result&&) = default;
-			~result() = default;
-
-			bool operator==(const result& rhs) const;
-
-			//! return the next row from the result or a "false" row, if there is no next row
-			sqlpp::raw_result_row_t next();
-			size_t num_cols() const;
-		};
-
-		class connection: public sqlpp::connection
-		{
-		public:
-			// A bunch of flags telling sqlpp11 which feature is support and which isn't
-
-			// join types
-			static constexpr bool _supports_inner_join = true;
-			static constexpr bool _supports_outer_join = true;
-			static constexpr bool _supports_left_outer_join = true;
-			static constexpr bool _supports_right_outer_join = true;
-
-			// functions
-			static constexpr bool _supports_avg = true;
-			static constexpr bool _supports_count = true;
-			static constexpr bool _supports_exists = true;
-			static constexpr bool _supports_like = true;
-			static constexpr bool _supports_in = true;
-			static constexpr bool _supports_is_null = true;
-			static constexpr bool _supports_is_not_null = true;
-			static constexpr bool _supports_max = true;
-			static constexpr bool _supports_min = true;
-			static constexpr bool _supports_not_in = true;
-			static constexpr bool _supports_sum = true;
-
-			// select
-			static constexpr bool _supports_group_by = true;
-			static constexpr bool _supports_having = true;
-			static constexpr bool _supports_limit = true;
-			static constexpr bool _supports_order_by = true;
-			static constexpr bool _supports_select_as_table = true;
-
-			static constexpr bool _supports_some = true;
-			static constexpr bool _supports_any = true;
-			static constexpr bool _use_concat_operator = false;
-			static constexpr bool _use_concat_function = true;
-
-			connection(/*whatever arguments you need*/);
-			connection(const connection&) = delete;
-			connection(connection&&) = delete;
-			connection& operator=(const connection&) = delete;
-			connection& operator=(connection&&) = delete;
-			~connection();
-
-			//! select returns a result (which can be iterated row by row)
-			result select(const std::string& query);
-
-			//! insert returns the last auto_incremented id (or zero, if there is none)
-			size_t insert(const std::string& query);
-
-			//! update returns the number of affected rows
-			size_t update(const std::string& query);
-
-			//! remove returns the number of removed rows
-			size_t remove(const std::string& query);
-
-			//! execute arbitrary command (e.g. create a table)
-			void execute(const std::string& command);
-
-			//! escape given string
-			std::string escape(const std::string& s) const;
-
-			//! call run on the argument
-			template<typename T>
-				auto run(const T& t) -> decltype(t.run(*this))
-				{
-					return t.run(*this);
-				}
-
-			//! start transaction
-			void start_transaction();
-
-			//! commit transaction (or throw transaction if the transaction has been finished already)
-			void commit_transaction();
-
-			//! rollback transaction with or without reporting the rollback (or throw if the transaction has been finished already)
-			void rollback_transaction(bool report);
-
-			//! report a rollback failure (will be called by transactions in case of a rollback failure in the destructor)
-			void report_rollback_failure(const std::string message) noexcept;
-		};
-	}
-}
-#endif
diff --git a/include/sqlpp11/column.h b/include/sqlpp11/column.h
index f1908e4d..1e5de615 100644
--- a/include/sqlpp11/column.h
+++ b/include/sqlpp11/column.h
@@ -44,6 +44,7 @@ namespace sqlpp
 	struct column_t: public ColumnSpec::_value_type::template operators<column_t<Table, ColumnSpec>>
 	{ 
 		using _is_column = std::true_type;
+		using _spec_t = ColumnSpec;
 		using _table = Table;
 		using _column_type = typename ColumnSpec::_column_type;
 		struct _value_type: ColumnSpec::_value_type
diff --git a/include/sqlpp11/detail/logic.h b/include/sqlpp11/detail/logic.h
new file mode 100644
index 00000000..72e3a318
--- /dev/null
+++ b/include/sqlpp11/detail/logic.h
@@ -0,0 +1,88 @@
+/*
+ * Copyright (c) 2013, 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_LOGIC_H
+#define SQLPP_DETAIL_LOGIC_H
+
+#include <type_traits>
+
+namespace sqlpp
+{
+	namespace detail
+	{
+		template<bool... b>
+			struct and_impl;
+
+		template<>
+			struct and_impl<>
+			{
+				static constexpr bool value = true;
+			};
+
+		template<bool... Rest>
+			struct and_impl<true, Rest...>
+			{
+				static constexpr bool value = and_impl<Rest...>::value;
+			};
+
+		template<bool... Rest>
+			struct and_impl<false, Rest...>
+			{
+				static constexpr bool value = false;
+			};
+
+		template<template<typename> class Predicate, typename... T>
+			using and_t = and_impl<Predicate<T>::value...>;
+
+		template<bool... b>
+			struct or_impl;
+
+		template<>
+			struct or_impl<>
+			{
+				static constexpr bool value = false;
+			};
+
+		template<bool... Rest>
+			struct or_impl<false, Rest...>
+			{
+				static constexpr bool value = or_impl<Rest...>::value;
+			};
+
+		template<bool... Rest>
+			struct or_impl<true, Rest...>
+			{
+				static constexpr bool value = true;
+			};
+
+		template<template<typename> class Predicate, typename... T>
+			using or_t = or_impl<Predicate<T>::value...>;
+
+	}
+}
+
+
+#endif
diff --git a/include/sqlpp11/detail/set.h b/include/sqlpp11/detail/set.h
deleted file mode 100644
index 2b1a153f..00000000
--- a/include/sqlpp11/detail/set.h
+++ /dev/null
@@ -1,201 +0,0 @@
-/*
- * Copyright (c) 2013, 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_SET_H
-#define SQLPP_DETAIL_SET_H
-
-#include <type_traits>
-#include <sqlpp11/vendor/wrong.h>
-
-namespace sqlpp
-{
-	namespace detail
-	{
-	template<typename... T>
-		struct make_set;
-
-		template<typename T>
-			class empty {};
-
-		template<typename SET, typename... T>
-			struct is_superset_of_impl
-			: std::false_type {};
-
-		template<typename SET>
-			struct is_superset_of_impl<SET>
-			: std::true_type {};
-
-		template<typename SET, typename T, typename... Rest>
-			struct is_superset_of_impl<SET, T, Rest...>
-			: std::integral_constant<bool, SET::template contains<T>::value and is_superset_of_impl<SET, Rest...>::value> {};
-
-		template<typename SET, typename... T>
-			struct is_disjunct_from_impl
-			: std::false_type {};
-
-		template<typename SET>
-			struct is_disjunct_from_impl<SET>
-			: std::true_type {};
-
-		template<typename SET, typename T, typename... Rest>
-			struct is_disjunct_from_impl<SET, T, Rest...>
-			: std::integral_constant<bool, not SET::template contains<T>::value and is_disjunct_from_impl<SET, Rest...>::value> {};
-
-	template<typename... Element>
-		struct set: empty<Element>...
-	{
-		struct size: std::integral_constant<size_t, sizeof...(Element)> {};
-
-		template<typename T>
-			struct contains
-			: std::integral_constant<bool, std::is_base_of<empty<T>, set>::value> {};
-
-		template<typename T>
-			struct is_superset_of
-			{
-				static_assert(::sqlpp::vendor::wrong_t<T>::value, "invalid argument for is_superset_of");
-			};
-
-		template<typename... T>
-			struct is_superset_of<set<T...>>
-			: is_superset_of_impl<set, T...>{};
-
-		template<typename T>
-			struct join
-			{
-				static_assert(::sqlpp::vendor::wrong_t<T>::value, "invalid argument for set::join");
-			};
-
-		template<typename... T>
-			struct join<set<T...>>
-			: make_set<Element..., T...> {};
-
-		template<typename T>
-			struct is_disjunct_from
-			{
-				static_assert(::sqlpp::vendor::wrong_t<T>::value, "invalid argument for is_disjunct_from");
-			};
-
-		template<typename... T>
-			struct is_disjunct_from<set<T...>>
-			: is_disjunct_from_impl<set, T...>{};
-
-		template<typename T>
-			struct is_subset_of
-			{
-				static_assert(::sqlpp::vendor::wrong_t<T>::value, "invalid argument for is_subset_of");
-			};
-
-		template<typename... T>
-			struct is_subset_of<set<T...>>
-			: is_superset_of_impl<set<T...>, Element...>{};
-
-		template<typename T>
-			struct equals
-			{
-				static_assert(::sqlpp::vendor::wrong_t<T>::value, "invalid argument for equals");
-			};
-
-		template<typename... T>
-			struct equals<set<T...>>
-			: std::integral_constant<bool, 
-			is_superset_of_impl<set<T...>, Element...>::value 
-				and
-				is_superset_of_impl<set<Element...>, T...>::value> {};
-
-		template<typename T, typename Enable = void>
-			struct insert
-			{
-				typedef set type;
-			};
-
-		template<typename T>
-			struct insert<T, typename std::enable_if<not set::template contains<T>::value>::type>
-			{
-				typedef set<Element..., T> type;
-			};
-
-		template<template<typename A> class Predicate, typename T, typename Enable = void>
-			struct insert_if
-			{
-				typedef set type;
-			};
-
-		template<template<typename A> class Predicate, typename T>
-			struct insert_if<Predicate, T, typename std::enable_if<not set::template contains<T>::value and Predicate<T>::value>::type>
-			{
-				typedef set<Element..., T> type;
-			};
-
-	};
-
-	template<>
-		struct make_set<>
-		{
-			typedef set<> type;
-		};
-
-	template<typename T, typename... Rest>
-		struct make_set<T, Rest...>
-		{
-			typedef typename make_set<Rest...>::type::template insert<T>::type type;
-		};
-
-	template<template<typename> class Predicate, typename... T>
-		struct make_set_if;
-
-	template<template<typename> class Predicate>
-		struct make_set_if<Predicate>
-		{
-			typedef set<> type;
-		};
-
-	template<template<typename> class Predicate, typename T, typename... Rest>
-		struct make_set_if<Predicate, T, Rest...>
-		{
-			typedef typename make_set_if<Predicate, Rest...>::type::template insert_if<Predicate, T>::type type;
-		};
-
-	template<template<typename> class Predicate, typename... T>
-		struct make_set_if_not
-		{
-			template<typename A>
-				struct InversePredicate
-				{
-					static constexpr bool value = not Predicate<A>::value;
-				};
-			using type = typename make_set_if<InversePredicate, T...>::type;
-		};
-
-	template<typename... T>
-		struct has_duplicates
-		: std::integral_constant<bool, make_set<T...>::type::size::value != sizeof...(T)> {};
-
-	}
-}
-
-
-#endif
diff --git a/include/sqlpp11/detail/type_set.h b/include/sqlpp11/detail/type_set.h
new file mode 100644
index 00000000..d367101f
--- /dev/null
+++ b/include/sqlpp11/detail/type_set.h
@@ -0,0 +1,159 @@
+/*
+ * Copyright (c) 2013, 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_TYPE_SET_H
+#define SQLPP_DETAIL_TYPE_SET_H
+
+#include <type_traits>
+#include <sqlpp11/vendor/wrong.h>
+#include <sqlpp11/detail/logic.h>
+
+namespace sqlpp
+{
+	namespace detail
+	{
+		// some forward declarations and helpers
+		template<typename... T>
+			struct make_set;
+
+		template<typename T>
+			class type_set_element {};
+
+		// A type set
+		template<typename... Element>
+			struct type_set: type_set_element<Element>...
+		{
+			using size = std::integral_constant<size_t, sizeof...(Element)>;
+
+			template<typename T>
+				using count = std::is_base_of<type_set_element<T>, type_set>;
+
+			template<typename T>
+				struct is_superset_of
+				{
+					static_assert(::sqlpp::vendor::wrong_t<T>::value, "invalid argument for is_superset_of");
+				};
+
+			template<typename... T>
+				struct is_superset_of<type_set<T...>>
+				: and_t<count, T...> {};
+
+			template<typename T>
+				struct join
+				{
+					static_assert(::sqlpp::vendor::wrong_t<T>::value, "invalid argument for type_set::join");
+				};
+
+			template<typename... T>
+				struct join<type_set<T...>>
+				: make_set<Element..., T...> {};
+
+			template<typename T>
+				struct is_subset_of
+				{
+					static_assert(::sqlpp::vendor::wrong_t<T>::value, "invalid argument for is_subset_of");
+				};
+
+			template<typename... T>
+				struct is_subset_of<type_set<T...>>
+				: type_set<T...>::template is_superset_of<type_set>{};
+
+			template<typename T>
+				struct is_disjunct_from
+				{
+					static_assert(::sqlpp::vendor::wrong_t<T>::value, "invalid argument for is_disjunct_from");
+				};
+
+			template<typename... T>
+				struct is_disjunct_from<type_set<T...>>
+				{
+					static constexpr bool value = not(or_t<type_set::count, T...>::value or or_t<type_set<T...>::template count, Element...>::value);
+				};
+
+			template<typename T, typename Enable = void>
+				struct insert
+				{
+					using type = type_set;
+				};
+
+			template<typename T>
+				struct insert<T, typename std::enable_if<not type_set::template count<T>::value>::type>
+				{
+					using type = type_set<Element..., T>;
+				};
+
+			template<template<typename A> class Predicate, typename T>
+				struct insert_if
+				{
+					using type = typename std::conditional<Predicate<T>::value,
+								type_set<Element..., T>,
+								type_set>::type;
+				};
+		};
+
+		template<>
+			struct make_set<>
+			{
+				using type = type_set<>;
+			};
+
+		template<typename T, typename... Rest>
+			struct make_set<T, Rest...>
+			{
+				using type = typename make_set<Rest...>::type::template insert<T>::type;
+			};
+
+		template<template<typename> class Predicate, typename... T>
+			struct make_set_if;
+
+		template<template<typename> class Predicate>
+			struct make_set_if<Predicate>
+			{
+				using type = type_set<>;
+			};
+
+		template<template<typename> class Predicate, typename T, typename... Rest>
+			struct make_set_if<Predicate, T, Rest...>
+			{
+				using type = typename make_set_if<Predicate, Rest...>::type::template insert_if<Predicate, T>::type;
+			};
+
+		template<template<typename> class Predicate, typename... T>
+			struct make_set_if_not
+			{
+				template<typename X>
+				using InversePredicate = std::integral_constant<bool, not Predicate<X>::value>;
+				using type = typename make_set_if<InversePredicate, T...>::type;
+			};
+
+		template<typename... T>
+			using has_duplicates = std::integral_constant<bool, make_set<T...>::type::size::value != sizeof...(T)>;
+
+	}
+}
+
+
+#endif
diff --git a/include/sqlpp11/insert.h b/include/sqlpp11/insert.h
index b8d9fdf5..918b3892 100644
--- a/include/sqlpp11/insert.h
+++ b/include/sqlpp11/insert.h
@@ -30,9 +30,11 @@
 #include <sqlpp11/type_traits.h>
 #include <sqlpp11/parameter_list.h>
 #include <sqlpp11/prepared_insert.h>
+#include <sqlpp11/default_value.h>
 #include <sqlpp11/vendor/column_list.h>
 #include <sqlpp11/vendor/noop.h>
 #include <sqlpp11/vendor/insert_list.h>
+#include <sqlpp11/vendor/assignment.h>
 #include <sqlpp11/vendor/insert_value_list.h>
 
 namespace sqlpp
diff --git a/include/sqlpp11/multi_column.h b/include/sqlpp11/multi_column.h
index 4d9cbc38..8cf50469 100644
--- a/include/sqlpp11/multi_column.h
+++ b/include/sqlpp11/multi_column.h
@@ -27,8 +27,9 @@
 #ifndef SQLPP_MULTI_COLUMN_H
 #define SQLPP_MULTI_COLUMN_H
 
-#include <sqlpp11/detail/make_expression_tuple.h>
 #include <sqlpp11/no_value.h>
+#include <sqlpp11/detail/make_expression_tuple.h>
+#include <sqlpp11/detail/logic.h>
 
 namespace sqlpp
 {
@@ -41,8 +42,7 @@ namespace sqlpp
 	template<typename AliasProvider, typename... NamedExpr>
 		struct multi_column_t<AliasProvider, std::tuple<NamedExpr...>>
 		{
-			using _named_expr_set = typename detail::make_set_if<is_named_expression_t, NamedExpr...>::type;
-			static_assert(_named_expr_set::size::value == sizeof...(NamedExpr), "multi_column parameters need to be named expressions");
+			static_assert(detail::and_t<is_named_expression_t, NamedExpr...>::value, "multi_column parameters need to be named expressions");
 
 			using _name_t = typename AliasProvider::_name_t;
 
diff --git a/include/sqlpp11/on.h b/include/sqlpp11/on.h
index e628f33c..68c1297d 100644
--- a/include/sqlpp11/on.h
+++ b/include/sqlpp11/on.h
@@ -28,9 +28,9 @@
 #define SQLPP_ON_H
 
 #include <sqlpp11/type_traits.h>
-#include <sqlpp11/detail/set.h>
 #include <sqlpp11/vendor/interpret_tuple.h>
 #include <sqlpp11/vendor/interpretable_list.h>
+#include <sqlpp11/detail/logic.h>
 
 namespace sqlpp
 {
@@ -41,8 +41,7 @@ namespace sqlpp
 			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...(Expr), "at least one expression argument required in on()");
-			using _valid_expressions = typename detail::make_set_if<is_expression_t, Expr...>::type;
-			static_assert(_valid_expressions::size::value == sizeof...(Expr), "at least one argument is not an expression in on()");
+			static_assert(detail::and_t<is_expression_t, Expr...>::value, "at least one argument is not an expression in on()");
 
 			template<typename E>
 				void add(E expr)
diff --git a/include/sqlpp11/select_flags.h b/include/sqlpp11/select_flags.h
index ffd15b30..3bcce768 100644
--- a/include/sqlpp11/select_flags.h
+++ b/include/sqlpp11/select_flags.h
@@ -29,7 +29,7 @@
 
 #include <sqlpp11/select_fwd.h>
 #include <sqlpp11/type_traits.h>
-#include <sqlpp11/detail/set.h>
+#include <sqlpp11/detail/type_set.h>
 #include <sqlpp11/vendor/interpret_tuple.h>
 #include <tuple>
 
diff --git a/include/sqlpp11/table.h b/include/sqlpp11/table.h
index 0066889d..afa9f95e 100644
--- a/include/sqlpp11/table.h
+++ b/include/sqlpp11/table.h
@@ -30,7 +30,7 @@
 #include <sqlpp11/type_traits.h>
 #include <sqlpp11/table_alias.h>
 #include <sqlpp11/column.h>
-#include <sqlpp11/detail/set.h>
+#include <sqlpp11/detail/type_set.h>
 #include <sqlpp11/join.h>
 #include <sqlpp11/no_value.h>
 
@@ -41,7 +41,7 @@ namespace sqlpp
 	template<typename Table, typename... ColumnSpec>
 	struct table_t: public table_base_t, public ColumnSpec::_name_t::template _member_t<column_t<Table, ColumnSpec>>...
 	{
-		using _table_set = detail::set<Table>; // Hint need a set here to be similar to a join (which always represents more than one table)
+		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 _all_columns = typename detail::make_set<column_t<Table, ColumnSpec>...>::type;
 		static_assert(_all_columns::size::value, "at least one column required per table");
 		using _required_insert_columns = typename detail::make_set_if<require_insert_t, column_t<Table, ColumnSpec>...>::type;
diff --git a/include/sqlpp11/table_alias.h b/include/sqlpp11/table_alias.h
index 2fa87c45..269d80b1 100644
--- a/include/sqlpp11/table_alias.h
+++ b/include/sqlpp11/table_alias.h
@@ -31,7 +31,7 @@
 #include <sqlpp11/interpret.h>
 #include <sqlpp11/type_traits.h>
 #include <sqlpp11/alias.h>
-#include <sqlpp11/detail/set.h>
+#include <sqlpp11/detail/type_set.h>
 
 namespace sqlpp
 {
@@ -42,7 +42,7 @@ namespace sqlpp
 	{
 		//FIXME: Need to add join functionality
 		using _is_table = std::true_type;
-		using _table_set = detail::set<table_alias_t>;
+		using _table_set = detail::type_set<table_alias_t>;
 
 		struct _value_type: Table::_value_type
 		{
diff --git a/include/sqlpp11/vendor/column_list.h b/include/sqlpp11/vendor/column_list.h
index 4659e1b2..e8bbdb9a 100644
--- a/include/sqlpp11/vendor/column_list.h
+++ b/include/sqlpp11/vendor/column_list.h
@@ -28,7 +28,7 @@
 #define SQLPP_COLUMN_LIST_H
 
 #include <sqlpp11/type_traits.h>
-#include <sqlpp11/detail/set.h>
+#include <sqlpp11/detail/logic.h>
 #include <sqlpp11/vendor/interpret_tuple.h>
 #include <sqlpp11/vendor/simple_column.h>
 
@@ -49,12 +49,10 @@ namespace sqlpp
 				static_assert(not ::sqlpp::detail::has_duplicates<Columns...>::value, "at least one duplicate argument detected in columns()");
 
 				// check for invalid columns
-				using _column_set = typename ::sqlpp::detail::make_set_if<is_column_t, Columns...>::type;
-				static_assert(_column_set::size::value == sizeof...(Columns), "at least one argument is not a column in columns()");
+				static_assert(::sqlpp::detail::and_t<is_column_t, Columns...>::value, "at least one argument is not a column in columns()");
 
 				// check for prohibited columns
-				using _prohibited_column_set = typename ::sqlpp::detail::make_set_if<must_not_insert_t, Columns...>::type;
-				static_assert(_prohibited_column_set::size::value == 0, "at least one column argument has a must_not_insert flag in its definition");
+				static_assert(not ::sqlpp::detail::or_t<must_not_insert_t, Columns...>::value, "at least one column argument has a must_not_insert flag in its definition");
 
 				std::tuple<simple_column_t<Columns>...> _columns;
 			};
diff --git a/include/sqlpp11/vendor/concat.h b/include/sqlpp11/vendor/concat.h
index 0aa524b9..232e92d2 100644
--- a/include/sqlpp11/vendor/concat.h
+++ b/include/sqlpp11/vendor/concat.h
@@ -29,7 +29,7 @@
 
 #include <sqlpp11/type_traits.h>
 #include <sqlpp11/vendor/interpret_tuple.h>
-#include <sqlpp11/detail/set.h>
+#include <sqlpp11/detail/logic.h>
 
 namespace sqlpp
 {
@@ -39,8 +39,7 @@ namespace sqlpp
 			struct concat_t: public First::_value_type::template operators<concat_t<First, Args...>>
 		{
 			static_assert(sizeof...(Args) > 0, "concat requires two arguments at least");
-			using _valid_args = typename ::sqlpp::detail::make_set_if_not<is_text_t, First, Args...>::type;
-			static_assert(_valid_args::size::value == 0, "at least one non-text argument detected in concat()");
+			static_assert(sqlpp::detail::and_t<is_text_t, First, Args...>::value, "at least one non-text argument detected in concat()");
 
 			struct _value_type: public First::_value_type::_base_value_type
 			{
diff --git a/include/sqlpp11/vendor/expression.h b/include/sqlpp11/vendor/expression.h
index df1c3f56..20de7a16 100644
--- a/include/sqlpp11/vendor/expression.h
+++ b/include/sqlpp11/vendor/expression.h
@@ -164,10 +164,12 @@ namespace sqlpp
 		template<typename Lhs, typename O, typename Rhs>
 			struct binary_expression_t: public O::_value_type::template 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, Rhs>;
+			using _parameter_tuple_t = std::tuple<_lhs_t, _rhs_t>;
 
-			binary_expression_t(Lhs lhs, Rhs rhs):
+			binary_expression_t(_lhs_t lhs, _rhs_t rhs):
 				_lhs(lhs), 
 				_rhs(rhs)
 			{}
@@ -178,8 +180,8 @@ namespace sqlpp
 			binary_expression_t& operator=(binary_expression_t&&) = default;
 			~binary_expression_t() = default;
 
-			Lhs _lhs;
-			Rhs _rhs;
+			_lhs_t _lhs;
+			_rhs_t _rhs;
 		};
 
 		template<typename Context, typename Lhs, typename O, typename Rhs>
diff --git a/include/sqlpp11/vendor/from.h b/include/sqlpp11/vendor/from.h
index da152d0d..11e8c999 100644
--- a/include/sqlpp11/vendor/from.h
+++ b/include/sqlpp11/vendor/from.h
@@ -27,11 +27,11 @@
 #ifndef SQLPP_FROM_H
 #define SQLPP_FROM_H
 
-#include <ostream>
 #include <sqlpp11/select_fwd.h>
 #include <sqlpp11/type_traits.h>
 #include <sqlpp11/vendor/interpretable_list.h>
 #include <sqlpp11/vendor/interpret_tuple.h>
+#include <sqlpp11/detail/logic.h>
 
 namespace sqlpp
 {
@@ -50,8 +50,7 @@ namespace sqlpp
 				static_assert(not ::sqlpp::detail::has_duplicates<TableOrJoin...>::value, "at least one duplicate argument detected in from()");
 
 				// check for invalid arguments
-				using _valid_expressions = typename ::sqlpp::detail::make_set_if<is_table_t, TableOrJoin...>::type;
-				static_assert(_valid_expressions::size::value == sizeof...(TableOrJoin), "at least one argument is not a table or join in from()");
+				static_assert(::sqlpp::detail::and_t<is_table_t, TableOrJoin...>::value, "at least one argument is not a table or join in from()");
 
 				// FIXME: Joins contain two tables. This is not being dealt with at the moment when looking at duplicates, for instance
 
diff --git a/include/sqlpp11/vendor/group_by.h b/include/sqlpp11/vendor/group_by.h
index db3e5d82..ca8e2e5e 100644
--- a/include/sqlpp11/vendor/group_by.h
+++ b/include/sqlpp11/vendor/group_by.h
@@ -32,7 +32,7 @@
 #include <sqlpp11/vendor/expression.h>
 #include <sqlpp11/vendor/interpret_tuple.h>
 #include <sqlpp11/vendor/interpretable_list.h>
-#include <sqlpp11/detail/set.h>
+#include <sqlpp11/detail/logic.h>
 
 namespace sqlpp
 {
@@ -52,8 +52,7 @@ namespace sqlpp
 				static_assert(not ::sqlpp::detail::has_duplicates<Expr...>::value, "at least one duplicate argument detected in group_by()");
 
 				// check for invalid expressions
-				using _valid_expressions = typename ::sqlpp::detail::make_set_if<is_expression_t, Expr...>::type;
-				static_assert(_valid_expressions::size::value == sizeof...(Expr), "at least one argument is not an expression in group_by()");
+				static_assert(::sqlpp::detail::and_t<is_expression_t, Expr...>::value, "at least one argument is not an expression in group_by()");
 
 				template<typename E>
 					void add(E expr)
diff --git a/include/sqlpp11/vendor/having.h b/include/sqlpp11/vendor/having.h
index 47fbc7cd..e9a474df 100644
--- a/include/sqlpp11/vendor/having.h
+++ b/include/sqlpp11/vendor/having.h
@@ -31,7 +31,7 @@
 #include <sqlpp11/vendor/expression.h>
 #include <sqlpp11/vendor/interpret_tuple.h>
 #include <sqlpp11/vendor/interpretable_list.h>
-#include <sqlpp11/detail/set.h>
+#include <sqlpp11/detail/logic.h>
 
 namespace sqlpp
 {
@@ -45,8 +45,7 @@ namespace sqlpp
 				using _parameter_tuple_t = std::tuple<Expr...>;
 
 				static_assert(_is_dynamic::value or sizeof...(Expr), "at least one expression argument required in having()");
-				using _valid_expressions = typename ::sqlpp::detail::make_set_if<is_expression_t, Expr...>::type;
-				static_assert(_valid_expressions::size::value == sizeof...(Expr), "at least one argument is not an expression in having()");
+				static_assert(::sqlpp::detail::and_t<is_expression_t, Expr...>::value, "at least one argument is not an expression in having()");
 
 				using _parameter_list_t = typename make_parameter_list_t<_parameter_tuple_t>::type;
 
diff --git a/include/sqlpp11/vendor/in.h b/include/sqlpp11/vendor/in.h
index c3e20b25..993a3288 100644
--- a/include/sqlpp11/vendor/in.h
+++ b/include/sqlpp11/vendor/in.h
@@ -30,7 +30,7 @@
 #include <sqlpp11/type_traits.h>
 #include <sqlpp11/boolean.h>
 #include <sqlpp11/vendor/in_fwd.h>
-#include <sqlpp11/detail/set.h>
+#include <sqlpp11/detail/type_set.h>
 
 namespace sqlpp
 {
diff --git a/include/sqlpp11/vendor/insert_list.h b/include/sqlpp11/vendor/insert_list.h
index db3af25e..2d30390f 100644
--- a/include/sqlpp11/vendor/insert_list.h
+++ b/include/sqlpp11/vendor/insert_list.h
@@ -28,10 +28,10 @@
 #define SQLPP_INSERT_LIST_H
 
 #include <sqlpp11/type_traits.h>
-#include <sqlpp11/detail/set.h>
 #include <sqlpp11/vendor/interpret_tuple.h>
 #include <sqlpp11/vendor/interpretable_list.h>
 #include <sqlpp11/vendor/simple_column.h>
+#include <sqlpp11/detail/logic.h>
 
 namespace sqlpp
 {
@@ -61,6 +61,10 @@ namespace sqlpp
 				using _is_insert_list = 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<Assignments...>;
+				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>...>;
 
 				// check for at least one order expression
 				static_assert(_is_dynamic::value or sizeof...(Assignments), "at least one select expression required in set()");
@@ -69,14 +73,13 @@ namespace sqlpp
 				static_assert(not ::sqlpp::detail::has_duplicates<Assignments...>::value, "at least one duplicate argument detected in set()");
 
 				// check for invalid assignments
-				using _assignment_set = typename ::sqlpp::detail::make_set_if<is_assignment_t, Assignments...>::type;
-				static_assert(_assignment_set::size::value == sizeof...(Assignments), "at least one argument is not an assignment in set()");
+				static_assert(sqlpp::detail::and_t<is_assignment_t, Assignments...>::value, "at least one argument is not an assignment in set()");
 
 				// check for prohibited assignments
-				using _prohibited_assignment_set = typename ::sqlpp::detail::make_set_if<must_not_insert_t, typename Assignments::_column_t...>::type;
-				static_assert(_prohibited_assignment_set::size::value == 0, "at least one assignment is prohibited by its column definition in set()");
+				static_assert(not sqlpp::detail::or_t<must_not_insert_t, typename Assignments::_column_t...>::value, "at least one assignment is prohibited by its column definition in set()");
 
 				insert_list_t(Assignments... assignment):
+					_assignments(assignment...),
 					_columns({assignment._lhs}...),
 					_values(assignment._rhs...)
 					{}
@@ -99,6 +102,7 @@ namespace sqlpp
 
 				std::tuple<simple_column_t<typename Assignments::_column_t>...> _columns;
 				std::tuple<typename Assignments::value_type...> _values;
+				std::tuple<Assignments...> _assignments; // FIXME: Need to replace _columns and _values by _assignments (connector-container requires assignments)
 				typename vendor::interpretable_list_t<Database> _dynamic_columns;
 				typename vendor::interpretable_list_t<Database> _dynamic_values;
 			};
diff --git a/include/sqlpp11/vendor/insert_value_list.h b/include/sqlpp11/vendor/insert_value_list.h
index f3d2b4ba..76fc1552 100644
--- a/include/sqlpp11/vendor/insert_value_list.h
+++ b/include/sqlpp11/vendor/insert_value_list.h
@@ -28,7 +28,7 @@
 #define SQLPP_INSERT_VALUE_LIST_H
 
 #include <sqlpp11/type_traits.h>
-#include <sqlpp11/detail/set.h>
+#include <sqlpp11/detail/logic.h>
 #include <sqlpp11/vendor/insert_value.h>
 #include <sqlpp11/vendor/interpret_tuple.h>
 
@@ -44,8 +44,7 @@ namespace sqlpp
 				static_assert(sizeof...(InsertValues), "at least one insert value required");
 
 				// check for invalid arguments
-				using _insert_values_set = typename ::sqlpp::detail::make_set_if<is_insert_value_t, InsertValues...>::type;
-				static_assert(_insert_values_set::size::value == sizeof...(InsertValues), "at least one argument is not an insert value");
+				static_assert(::sqlpp::detail::and_t<is_insert_value_t, InsertValues...>::value, "at least one argument is not an insert value");
 
 				using _value_tuple_t = std::tuple<InsertValues...>;
 
diff --git a/include/sqlpp11/vendor/is_null.h b/include/sqlpp11/vendor/is_null.h
index 1bbafb64..7b7dab61 100644
--- a/include/sqlpp11/vendor/is_null.h
+++ b/include/sqlpp11/vendor/is_null.h
@@ -29,7 +29,7 @@
 
 #include <sqlpp11/boolean.h>
 #include <sqlpp11/type_traits.h>
-#include <sqlpp11/detail/set.h>
+#include <sqlpp11/detail/type_set.h>
 
 namespace sqlpp
 {
diff --git a/include/sqlpp11/vendor/like.h b/include/sqlpp11/vendor/like.h
index 8647cb08..6ad5d9a9 100644
--- a/include/sqlpp11/vendor/like.h
+++ b/include/sqlpp11/vendor/like.h
@@ -29,7 +29,7 @@
 
 #include <sqlpp11/boolean.h>
 #include <sqlpp11/type_traits.h>
-#include <sqlpp11/detail/set.h>
+#include <sqlpp11/detail/type_set.h>
 
 namespace sqlpp
 {
diff --git a/include/sqlpp11/vendor/order_by.h b/include/sqlpp11/vendor/order_by.h
index 34ee6c1d..fd58485f 100644
--- a/include/sqlpp11/vendor/order_by.h
+++ b/include/sqlpp11/vendor/order_by.h
@@ -51,8 +51,7 @@ namespace sqlpp
 				static_assert(not ::sqlpp::detail::has_duplicates<Expr...>::value, "at least one duplicate argument detected in order_by()");
 
 				// check for invalid order expressions
-				using _valid_expressions = typename ::sqlpp::detail::make_set_if<is_sort_order_t, Expr...>::type;
-				static_assert(_valid_expressions::size::value == sizeof...(Expr), "at least one argument is not a sort order expression in order_by()");
+				static_assert(::sqlpp::detail::and_t<is_sort_order_t, Expr...>::value, "at least one argument is not a sort order expression in order_by()");
 
 				template<typename E>
 					void add(E expr)
diff --git a/include/sqlpp11/vendor/select_column_list.h b/include/sqlpp11/vendor/select_column_list.h
index 82d28111..ce421e8f 100644
--- a/include/sqlpp11/vendor/select_column_list.h
+++ b/include/sqlpp11/vendor/select_column_list.h
@@ -31,13 +31,13 @@
 #include <sqlpp11/result_row.h>
 #include <sqlpp11/select_fwd.h>
 #include <sqlpp11/table.h>
-#include <sqlpp11/vendor/expression_fwd.h>
 #include <sqlpp11/no_value.h>
 #include <sqlpp11/vendor/field.h>
+#include <sqlpp11/vendor/expression_fwd.h>
 #include <sqlpp11/vendor/select_pseudo_table.h>
 #include <sqlpp11/vendor/named_interpretable.h>
 #include <sqlpp11/vendor/interpret_tuple.h>
-#include <sqlpp11/detail/set.h>
+#include <sqlpp11/detail/type_set.h>
 
 namespace sqlpp
 {
@@ -149,9 +149,8 @@ namespace sqlpp
 
 				// check for invalid select expressions
 				template<typename T>
-					struct is_valid_expression_t: public std::integral_constant<bool, is_named_expression_t<T>::value or is_multi_column_t<T>::value> {};
-				using _valid_expressions = typename ::sqlpp::detail::make_set_if<is_valid_expression_t, NamedExpr...>::type;
-				static_assert(_valid_expressions::size::value == sizeof...(NamedExpr), "at least one argument is not a named expression");
+					using is_valid_expression_t = std::integral_constant<bool, is_named_expression_t<T>::value or is_multi_column_t<T>::value>;
+				static_assert(::sqlpp::detail::and_t<is_valid_expression_t, NamedExpr...>::value, "at least one argument is not a named expression");
 
 				// check for duplicate select expression names
 				static_assert(not ::sqlpp::detail::has_duplicates<typename NamedExpr::_name_t...>::value, "at least one duplicate name detected");
diff --git a/include/sqlpp11/vendor/select_flag_list.h b/include/sqlpp11/vendor/select_flag_list.h
index 7833bef1..a167e4fc 100644
--- a/include/sqlpp11/vendor/select_flag_list.h
+++ b/include/sqlpp11/vendor/select_flag_list.h
@@ -30,7 +30,7 @@
 #include <sqlpp11/select_fwd.h>
 #include <sqlpp11/type_traits.h>
 #include <sqlpp11/select_flags.h>
-#include <sqlpp11/detail/set.h>
+#include <sqlpp11/detail/type_set.h>
 #include <sqlpp11/vendor/interpret_tuple.h>
 #include <tuple>
 
@@ -57,8 +57,7 @@ namespace sqlpp
 				static_assert(not ::sqlpp::detail::has_duplicates<Flag...>::value, "at least one duplicate argument detected in select flag list");
 
 				// check for invalid order expressions
-				using _valid_flags = typename ::sqlpp::detail::make_set_if<is_select_flag_t, Flag...>::type;
-				static_assert(_valid_flags::size::value == sizeof...(Flag), "at least one argument is not a select flag in select flag list");
+				static_assert(::sqlpp::detail::and_t<is_select_flag_t, Flag...>::value, "at least one argument is not a select flag in select flag list");
 
 				template<typename E>
 					void add(E expr)
diff --git a/include/sqlpp11/vendor/update_list.h b/include/sqlpp11/vendor/update_list.h
index 435a2d83..a58e92fd 100644
--- a/include/sqlpp11/vendor/update_list.h
+++ b/include/sqlpp11/vendor/update_list.h
@@ -28,7 +28,7 @@
 #define SQLPP_UPDATE_LIST_H
 
 #include <sqlpp11/type_traits.h>
-#include <sqlpp11/detail/set.h>
+#include <sqlpp11/detail/type_set.h>
 #include <sqlpp11/vendor/interpret_tuple.h>
 #include <sqlpp11/vendor/interpretable_list.h>
 
@@ -50,12 +50,10 @@ namespace sqlpp
 				static_assert(not ::sqlpp::detail::has_duplicates<Assignments...>::value, "at least one duplicate argument detected in set()");
 
 				// check for invalid assignments
-				using _assignment_set = typename ::sqlpp::detail::make_set_if<is_assignment_t, Assignments...>::type;
-				static_assert(_assignment_set::size::value == sizeof...(Assignments), "at least one argument is not an assignment in set()");
+				static_assert(::sqlpp::detail::and_t<is_assignment_t, Assignments...>::value, "at least one argument is not an assignment in set()");
 
 				// check for prohibited assignments
-				using _prohibited_assignment_set = typename ::sqlpp::detail::make_set_if<must_not_update_t, typename Assignments::_column_t...>::type;
-				static_assert(_prohibited_assignment_set::size::value == 0, "at least one assignment is prohibited by its column definition in set()");
+				static_assert(not ::sqlpp::detail::or_t<must_not_update_t, typename Assignments::_column_t...>::value, "at least one assignment is prohibited by its column definition in set()");
 
 				template<typename Assignment>
 					void add(Assignment assignment)
diff --git a/include/sqlpp11/vendor/using.h b/include/sqlpp11/vendor/using.h
index 410a2cfe..7f98b821 100644
--- a/include/sqlpp11/vendor/using.h
+++ b/include/sqlpp11/vendor/using.h
@@ -28,9 +28,9 @@
 #define SQLPP_USING_H
 
 #include <sqlpp11/type_traits.h>
-#include <sqlpp11/detail/set.h>
 #include <sqlpp11/vendor/interpretable_list.h>
 #include <sqlpp11/vendor/interpret_tuple.h>
+#include <sqlpp11/detail/type_set.h>
 
 namespace sqlpp
 {
@@ -49,8 +49,7 @@ namespace sqlpp
 				static_assert(not ::sqlpp::detail::has_duplicates<Table...>::value, "at least one duplicate argument detected in using()");
 
 				// check for invalid arguments
-				using _valid_expressions = typename ::sqlpp::detail::make_set_if<is_table_t, Table...>::type;
-				static_assert(_valid_expressions::size::value == sizeof...(Table), "at least one argument is not an table in using()");
+				static_assert(::sqlpp::detail::and_t<is_table_t, Table...>::value, "at least one argument is not an table in using()");
 
 
 				template<typename T>
diff --git a/include/sqlpp11/vendor/where.h b/include/sqlpp11/vendor/where.h
index e4e87505..72de65fa 100644
--- a/include/sqlpp11/vendor/where.h
+++ b/include/sqlpp11/vendor/where.h
@@ -31,7 +31,7 @@
 #include <sqlpp11/select_fwd.h>
 #include <sqlpp11/vendor/expression.h>
 #include <sqlpp11/type_traits.h>
-#include <sqlpp11/detail/set.h>
+#include <sqlpp11/detail/logic.h>
 #include <sqlpp11/vendor/interpret_tuple.h>
 #include <sqlpp11/vendor/interpretable_list.h>
 #include <sqlpp11/parameter_list.h>
@@ -48,8 +48,7 @@ namespace sqlpp
 				using _parameter_tuple_t = std::tuple<Expr...>;
 
 				static_assert(_is_dynamic::value or sizeof...(Expr), "at least one expression argument required in where()");
-				using _valid_expressions = typename sqlpp::detail::make_set_if<is_expression_t, Expr...>::type;
-				static_assert(_valid_expressions::size::value == sizeof...(Expr), "at least one argument is not an expression in where()");
+				static_assert(sqlpp::detail::and_t<is_expression_t, Expr...>::value, "at least one argument is not an expression in where()");
 
 				using _parameter_list_t = typename make_parameter_list_t<_parameter_tuple_t>::type;
 
diff --git a/tests/CMakeLists.txt b/tests/CMakeLists.txt
index b9798885..b2a56c15 100644
--- a/tests/CMakeLists.txt
+++ b/tests/CMakeLists.txt
@@ -14,8 +14,10 @@ build_and_run(SelectTest)
 build_and_run(FunctionTest)
 build_and_run(PreparedTest)
 
+find_package(PythonInterp REQUIRED)
+
 add_custom_command(
 	OUTPUT ${CMAKE_CURRENT_LIST_DIR}/Sample.h 
-	COMMAND ${CMAKE_SOURCE_DIR}/scripts/ddl2cpp ${CMAKE_CURRENT_LIST_DIR}/sample.sql Sample test
+	COMMAND ${PYTHON_EXECUTABLE} ${CMAKE_SOURCE_DIR}/scripts/ddl2cpp ${CMAKE_CURRENT_LIST_DIR}/sample.sql Sample test
 	)