diff --git a/include/sqlpp11/functions.h b/include/sqlpp11/functions.h
index 6c13fd7e..ff561e2a 100644
--- a/include/sqlpp11/functions.h
+++ b/include/sqlpp11/functions.h
@@ -45,6 +45,8 @@
 
 namespace sqlpp
 {
+#warning add a value_or_null method that yields a type that can be NULL or have a value (very similar to an optional)
+#warning add a template<typename Db> bool_expression which takes any bool expression as constructor argument
 	template<typename T>
 		auto value(T t) -> wrap_operand_t<T>
 		{
diff --git a/tests/MockDb.h b/tests/MockDb.h
index 8642208e..3356c214 100644
--- a/tests/MockDb.h
+++ b/tests/MockDb.h
@@ -30,6 +30,7 @@
 #include <sqlpp11/serializer_context.h>
 #include <sqlpp11/connection.h>
 
+#warning add serialization to run methods to increase the number of tests
 template<bool enforceNullResultTreatment>
 struct MockDbT: public sqlpp::connection
 {