diff --git a/connector_api/connection.h b/connector_api/connection.h
index 14d22dd0..e3b7a4dc 100644
--- a/connector_api/connection.h
+++ b/connector_api/connection.h
@@ -51,6 +51,10 @@ namespace sqlpp
 		class connection: public sqlpp::connection // this inheritance helps with ADL for dynamic_select, for instance
 		{
 		public:
+			using _traits = ::sqlpp::make_traits<::sqlpp::no_value_t, 
+								::sqlpp::tag::enforce_null_result_treatment // If that is what you really want, leave it out otherwise
+							>;
+
 			using _prepared_statement_t = << handle to a prepared statement of the database >>;
 			using _serializer_context_t = << This context is used to serialize a statement >>
 			using _interpreter_context_t = << This context is used interpret a statement >>;
diff --git a/include/sqlpp11/boolean.h b/include/sqlpp11/boolean.h
index 2b0d147c..0ed43af3 100644
--- a/include/sqlpp11/boolean.h
+++ b/include/sqlpp11/boolean.h
@@ -41,6 +41,7 @@ namespace sqlpp
 		// boolean value type
 		struct boolean
 		{
+			using _traits = make_traits<boolean, ::sqlpp::tag::is_boolean, ::sqlpp::tag::is_expression>;
 			using _tag = ::sqlpp::tag::is_boolean;
 			using _cpp_value_type = bool;
 
@@ -122,7 +123,7 @@ namespace sqlpp
 					using _field_methods_t = field_methods_t<_result_field_t<Db, FieldSpec>>;
 
 					using _traits = make_traits<integral,
-								typename std::conditional<_field_methods_t::_null_is_trivial, ::sqlpp::tag::null_is_trivial_value, void>::type>;
+								tag_if<tag::null_is_trivial_value, _field_methods_t::_null_is_trivial>>;
 
 					struct _recursive_traits
 					{
diff --git a/include/sqlpp11/field_spec.h b/include/sqlpp11/field_spec.h
index aaea3690..ee2ae33c 100644
--- a/include/sqlpp11/field_spec.h
+++ b/include/sqlpp11/field_spec.h
@@ -35,9 +35,9 @@ namespace sqlpp
 		struct field_spec_t
 		{ 
 			using _traits = make_traits<ValueType, tag::is_noop, 
-						typename std::conditional<CanBeNull, tag::can_be_null, void>::type,
-						typename std::conditional<NullIsTrivialValue, tag::null_is_trivial_value, void>::type
-						>;
+						tag_if<tag::can_be_null, CanBeNull>,
+						tag_if<tag::null_is_trivial_value, NullIsTrivialValue>
+							>;
 			using _recursive_traits = make_recursive_traits<>;
 
 			using _name_t = NameType;
diff --git a/include/sqlpp11/floating_point.h b/include/sqlpp11/floating_point.h
index b740fbb8..da5f3943 100644
--- a/include/sqlpp11/floating_point.h
+++ b/include/sqlpp11/floating_point.h
@@ -40,6 +40,7 @@ namespace sqlpp
 		// floating_point value type
 		struct floating_point
 		{
+			using _traits = make_traits<floating_point, ::sqlpp::tag::is_floating_point, ::sqlpp::tag::is_expression>;
 			using _tag = ::sqlpp::tag::is_floating_point;
 			using _cpp_value_type = double;
 
@@ -121,7 +122,7 @@ namespace sqlpp
 					using _field_methods_t = field_methods_t<_result_field_t<Db, FieldSpec>>;
 
 					using _traits = make_traits<integral,
-								typename std::conditional<_field_methods_t::_null_is_trivial, ::sqlpp::tag::null_is_trivial_value, void>::type>;
+								tag_if<tag::null_is_trivial_value, _field_methods_t::_null_is_trivial>>;
 
 					struct _recursive_traits
 					{
diff --git a/include/sqlpp11/integral.h b/include/sqlpp11/integral.h
index 287fa891..8dad0912 100644
--- a/include/sqlpp11/integral.h
+++ b/include/sqlpp11/integral.h
@@ -42,7 +42,7 @@ namespace sqlpp
 		// integral value type
 		struct integral
 		{
-			using _traits = make_traits<integral, ::sqlpp::tag::is_expression>;
+			using _traits = make_traits<integral, ::sqlpp::tag::is_integral, ::sqlpp::tag::is_expression>;
 			using _tag = ::sqlpp::tag::is_integral;
 			using _cpp_value_type = int64_t;
 
@@ -123,7 +123,7 @@ namespace sqlpp
 					using _field_methods_t = field_methods_t<_result_field_t<Db, FieldSpec>>;
 
 					using _traits = make_traits<integral,
-								typename std::conditional<_field_methods_t::_null_is_trivial, ::sqlpp::tag::null_is_trivial_value, void>::type>;
+								tag_if<tag::null_is_trivial_value, _field_methods_t::_null_is_trivial>>;
 
 					struct _recursive_traits
 					{
diff --git a/include/sqlpp11/select_pseudo_table.h b/include/sqlpp11/select_pseudo_table.h
index 3feb809a..e803fa59 100644
--- a/include/sqlpp11/select_pseudo_table.h
+++ b/include/sqlpp11/select_pseudo_table.h
@@ -43,7 +43,7 @@ namespace sqlpp
 			using _traits = make_traits<value_type_of<NamedExpr>, 
 						tag::must_not_insert, 
 						tag::must_not_update,
-						typename std::conditional<_can_be_null or _depends_on_outer_table, tag::can_be_null, void>::type
+						tag_if<tag::can_be_null, _can_be_null or _depends_on_outer_table>
 							>;
 		};
 
diff --git a/include/sqlpp11/statement.h b/include/sqlpp11/statement.h
index cce00ab5..64d17e82 100644
--- a/include/sqlpp11/statement.h
+++ b/include/sqlpp11/statement.h
@@ -98,12 +98,7 @@ namespace sqlpp
 					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>;
+				using _traits = make_traits<_value_type, tag_if<tag::is_expression, not std::is_same<_value_type, no_value_t>::value>>;
 
 				struct _recursive_traits
 				{
@@ -135,8 +130,8 @@ namespace sqlpp
 
 		using _traits = make_traits<value_type_of<_policies_t>,
 					::sqlpp::tag::is_select, 
-					tag::is_expression_if<typename _policies_t::_is_expression>, 
-					tag::is_named_expression_if<typename _policies_t::_is_expression>,
+					tag_if<tag::is_expression, is_expression_t<_policies_t>::value>, 
+					tag_if<tag::is_named_expression, is_expression_t<_policies_t>::value>,
 					tag::requires_braces>;
 		using _recursive_traits = typename _policies_t::_recursive_traits;
 		using _used_outer_tables = typename _policies_t::_all_provided_outer_tables;
diff --git a/include/sqlpp11/table_alias.h b/include/sqlpp11/table_alias.h
index 58f09415..7cc58a9f 100644
--- a/include/sqlpp11/table_alias.h
+++ b/include/sqlpp11/table_alias.h
@@ -39,7 +39,7 @@ namespace sqlpp
 		struct table_alias_t: public ColumnSpec::_name_t::template _member_t<column_t<AliasProvider, ColumnSpec>>...
 	{
 		//FIXME: Need to add join functionality
-		using _traits = make_traits<value_type_of<Table>, tag::is_table, tag::is_alias, tag::is_named_expression_if<is_expression_t<Table>>>;
+		using _traits = make_traits<value_type_of<Table>, tag::is_table, tag::is_alias, tag_if<tag::is_named_expression, is_expression_t<Table>::value>>;
 
 		struct _recursive_traits
 		{
diff --git a/include/sqlpp11/text.h b/include/sqlpp11/text.h
index 2d9b0087..e90d5e6c 100644
--- a/include/sqlpp11/text.h
+++ b/include/sqlpp11/text.h
@@ -40,6 +40,7 @@ namespace sqlpp
 		// text value type
 		struct text
 		{
+			using _traits = make_traits<text, ::sqlpp::tag::is_text, ::sqlpp::tag::is_expression>;
 			using _tag = ::sqlpp::tag::is_text;
 			using _cpp_value_type = std::string;
 
@@ -121,7 +122,7 @@ namespace sqlpp
 					using _field_methods_t = field_methods_t<_result_field_t<Db, FieldSpec>>;
 
 					using _traits = make_traits<integral,
-								typename std::conditional<_field_methods_t::_null_is_trivial, ::sqlpp::tag::null_is_trivial_value, void>::type>;
+								tag_if<tag::null_is_trivial_value, _field_methods_t::_null_is_trivial>>;
 
 					struct _recursive_traits
 					{
diff --git a/include/sqlpp11/type_traits.h b/include/sqlpp11/type_traits.h
index 47f04a99..659d7bab 100644
--- a/include/sqlpp11/type_traits.h
+++ b/include/sqlpp11/type_traits.h
@@ -82,16 +82,6 @@ namespace sqlpp
 	SQLPP_VALUE_TRAIT_GENERATOR(is_wrapped_value);
 	SQLPP_VALUE_TRAIT_GENERATOR(is_expression);
 	SQLPP_VALUE_TRAIT_GENERATOR(is_named_expression);
-	namespace tag
-	{
-		template<typename C>
-			using is_named_expression_if = typename std::conditional<C::value, tag::is_named_expression, void>::type;
-	}
-	namespace tag
-	{
-		template<typename C>
-			using is_expression_if = typename std::conditional<C::value, tag::is_expression, void>::type;
-	}
 	SQLPP_VALUE_TRAIT_GENERATOR(is_multi_expression);
 	SQLPP_VALUE_TRAIT_GENERATOR(is_alias);
 	SQLPP_VALUE_TRAIT_GENERATOR(is_select_flag);
@@ -139,12 +129,12 @@ namespace sqlpp
 
 	SQLPP_VALUE_TRAIT_GENERATOR(enforce_null_result_treatment);
 
+	template<typename Tag, bool Condition>
+		using tag_if = typename std::conditional<Condition, Tag, void>::type;
+
 	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>
diff --git a/tests/MockDb.h b/tests/MockDb.h
index a123d857..8642208e 100644
--- a/tests/MockDb.h
+++ b/tests/MockDb.h
@@ -33,8 +33,9 @@
 template<bool enforceNullResultTreatment>
 struct MockDbT: public sqlpp::connection
 {
-	using _traits = ::sqlpp::make_traits<::sqlpp::no_value_t,
-			 	typename std::conditional<enforceNullResultTreatment, ::sqlpp::tag::enforce_null_result_treatment, void>::type>;
+	using _traits = ::sqlpp::make_traits<::sqlpp::no_value_t, 
+						::sqlpp::tag_if<::sqlpp::tag::enforce_null_result_treatment, enforceNullResultTreatment>
+					>;
 
 	struct _serializer_context_t
 	{