work on order by began

parser.h

@@ -34,6 +34,7 @@ namespace usql {
 	save_table,
 	drop_table,
 	column_name,
+	column_order,
 	column_value,
 	function,
 	column_def,
@@ -52,6 +53,15 @@ namespace usql {
 	ColNameNode(const std::string col_name) : Node(NodeType::column_name), name(col_name) {}
     };
 
+    struct ColOrderNode : Node {
+	std::string col_name;
+	int col_index;
+	bool ascending;
+
+	ColOrderNode(const std::string name, bool asc) : Node(NodeType::column_order), col_name(name), col_index(-1), ascending(asc) {}
+	ColOrderNode(int index, bool asc) : Node(NodeType::column_name), col_name(""), col_index(index), ascending(asc) {}
+    };
+
     struct SelectColNode : Node {
         std::unique_ptr<Node>	value;
         std::string name;
@@ -216,9 +226,10 @@ namespace usql {
 	std::string table_name;
 	std::unique_ptr<std::vector<SelectColNode>> cols_names;
 	std::unique_ptr<Node> where;
+	std::vector<ColOrderNode> order_by;
 
-	SelectFromTableNode(std::string name, std::unique_ptr<std::vector<SelectColNode>> names, std::unique_ptr<Node> where_clause) :
-	Node(NodeType::select_from), table_name(name), cols_names(std::move(names)), where(std::move(where_clause)) {}
+	SelectFromTableNode(std::string name, std::unique_ptr<std::vector<SelectColNode>> names, std::unique_ptr<Node> where_clause, std::vector<ColOrderNode> orderby) :
+	Node(NodeType::select_from), table_name(name), cols_names(std::move(names)), where(std::move(where_clause)), order_by(orderby) {}
     };
 
     struct CreateTableAsSelectNode : Node {
@@ -292,6 +303,8 @@ namespace usql {
 	std::unique_ptr<Node> parse_update_table();
 
 	std::unique_ptr<Node> parse_where_clause();
+	std::vector<ColOrderNode>  parse_orderby_clause();
+
 	std::unique_ptr<Node> parse_operand_node();
 	std::unique_ptr<Node> parse_value();
 	RelationalOperatorType parse_relational_operator();