Dynamic Order by (SQL)

dynamic_orderBy.sql

-- Make sure whatever _order is passed, is selected in SELECT.

@delimiter %%%;
CREATE PROCEDURE prime1(_order VARCHAR(32)) NOT DETERMINISTIC READS SQL DATA
    BEGIN
                  SET @order = _order;
                  SELECT ID, TITLE, SUMMARY  FROM articles a ORDER BY                  
                    CASE WHEN _order = 'SUMMARY ASC' THEN SUMMARY END ASC,
                    CASE WHEN _order = 'ID ASC' THEN ID END ASC,
                    CASE WHEN _order = 'TITLE ASC' THEN TITLE END ASC,
                    CASE WHEN _order = 'SUMMARY DESC' THEN SUMMARY END DESC,
                    CASE WHEN _order = 'ID DESC' THEN ID END DESC,
                    CASE WHEN _order = 'TITLE DESC' THEN TITLE END DESC
                  ;
        END;
        %%%
@delimiter ;
%%%