ALTER PROCEDURE [dbo].[sp2_GetAllCategories] @SortDirection varchar (5) = NULL, @SortExpression varchar(50) = NULL AS BEGIN SET NOCOUNT ON; DECLARE @sql varchar(Max) SET @sql = 'SELECT * FROM Categories ORDER BY ' + ISNULL(@SortExpression, 'CategoryNameEN') + ' ' + ISNULL(@SortDirection, 'ASC') EXEC (@sql) END