added returning token for insert query

include/matador/query/intermediates/query_into_intermediate.hpp

@@ -2,24 +2,32 @@
 #define QUERY_INTO_INTERMEDIATE_HPP
 
 #include "matador/query/intermediates/executable_query.hpp"
+#include "matador/query/intermediates/fetchable_query.hpp"
 
 #include "matador/query/value_extractor.hpp"
 
 #include "matador/utils/placeholder.hpp"
 
 namespace matador::query {
+class table_column;
 
-class query_into_intermediate : public query_intermediate
-{
+class query_values_intermediate : public executable_query {
+public:
+  using executable_query::executable_query;
+
+  fetchable_query returning(const table_column &col);
+};
+
+class query_into_intermediate : public query_intermediate {
 public:
   using query_intermediate::query_intermediate;
 
-  executable_query values(std::initializer_list<std::variant<utils::placeholder, utils::database_type>> values);
-  executable_query values(std::vector<std::variant<utils::placeholder, utils::database_type>> &&values);
-  executable_query values(std::vector<utils::placeholder> &&values);
-  executable_query values(std::vector<utils::database_type> &&values);
+  query_values_intermediate values(std::initializer_list<std::variant<utils::placeholder, utils::database_type>> values);
+  query_values_intermediate values(std::vector<std::variant<utils::placeholder, utils::database_type>> &&values);
+  query_values_intermediate values(std::vector<utils::placeholder> &&values);
+  query_values_intermediate values(std::vector<utils::database_type> &&values);
   template<class Type>
-  executable_query values(const Type &obj) {
+  query_values_intermediate values(const Type &obj) {
     return values(value_extractor::extract(obj));
   }
 };

include/matador/query/internal/query_parts.hpp

@@ -317,8 +317,7 @@ private:
 /**
  * Represents the SQL VALUES part
  */
-class query_values_part final : public query_part
-{
+class query_values_part final : public query_part {
 public:
   explicit query_values_part(std::vector<std::variant<utils::placeholder, utils::database_type>> &&values);
 
@@ -331,6 +330,19 @@ private:
   std::vector<std::variant<utils::placeholder, utils::database_type>> values_;
 };
 
+class query_returning_part final : public query_part {
+public:
+  explicit query_returning_part(std::vector<table_column> columns);
+
+  [[nodiscard]] const std::vector<table_column>& columns() const;
+
+private:
+  void accept(query_part_visitor &visitor) override;
+
+private:
+  std::vector<table_column> columns_;
+};
+
 class query_update_part final : public query_part
 {
 public:

include/matador/query/query_builder.hpp

@@ -44,7 +44,6 @@ protected:
   void visit(internal::query_drop_key_constraint_part_by_name &part) override;
   void visit(internal::query_drop_key_constraint_part_by_constraint &part) override;
 
-protected:
   void visit(internal::query_select_part &part) override;
   void visit(internal::query_from_part &part) override;
   void visit(internal::query_join_table_part &part) override;
@@ -57,9 +56,11 @@ protected:
   void visit(internal::query_order_by_desc_part &part) override;
   void visit(internal::query_offset_part &part) override;
   void visit(internal::query_limit_part &part) override;
+
   void visit(internal::query_insert_part &part) override;
   void visit(internal::query_into_part &part) override;
   void visit(internal::query_values_part &part) override;
+  void visit(internal::query_returning_part &part) override;
 
   void visit(internal::query_update_part &part) override;
   void visit(internal::query_set_part &part) override;

include/matador/query/query_part_visitor.hpp

@@ -4,7 +4,9 @@
 namespace matador::query {
 
 namespace internal {
+// Alter common
 class query_alter_part;
+// Alter table
 class query_alter_table_part;
 class query_add_key_constraint_part;
 class query_drop_key_constraint_part_by_name;
@@ -13,6 +15,7 @@ class query_add_foreign_key_constraint_part;
 class query_add_constraint_part_by_constraint;
 class query_add_foreign_key_reference_part;
 class query_add_primary_key_constraint_part;
+// Select
 class query_select_part;
 class query_from_part;
 class query_join_table_part;
@@ -25,20 +28,30 @@ class query_order_by_asc_part;
 class query_order_by_desc_part;
 class query_offset_part;
 class query_limit_part;
+// Insert
 class query_insert_part;
 class query_into_part;
 class query_values_part;
+class query_returning_part;
+// Update
 class query_update_part;
 class query_set_part;
+// Delete
 class query_delete_part;
 class query_delete_from_part;
+// Create common
 class query_create_part;
+// Create table
 class query_create_table_part;
 class query_create_table_columns_part;
 class query_create_table_constraints_part;
+// Create schema
 class query_create_schema_part;
+// Drop common
 class query_drop_part;
+// Drop table
 class query_drop_table_part;
+// Drop schema
 class query_drop_schema_part;
 }
 
@@ -72,6 +85,7 @@ public:
   virtual void visit(internal::query_insert_part &part) = 0;
   virtual void visit(internal::query_into_part &part) = 0;
   virtual void visit(internal::query_values_part &part) = 0;
+  virtual void visit(internal::query_returning_part &part) = 0;
 
   virtual void visit(internal::query_update_part &part) = 0;
   virtual void visit(internal::query_set_part &part) = 0;

include/matador/query/query_utils.hpp

@@ -12,6 +12,7 @@ class dialect;
 namespace matador::query {
 class table_column;
 
+void prepare_column(std::string &out, const sql::dialect& d, const table_column &col);
 [[nodiscard]] std::string prepare_identifier(const sql::dialect& d, const table_column &col);
 [[nodiscard]] std::string prepare_criteria(const sql::dialect& d, const table_column &col);
 }