## mysql case when使用
SELECT order_no, case is_test when 0 then '否' when 1 then '是' end as '是否测试' from `tbl_order` WHERE `order_no` in ( 'afsd122112121' );
SELECT order_no, case is_test when 0 then '否' else '是' end as '是否测试' from `tbl_order` WHERE `order_no` in ( 'afsd122112121' );
SELECT order_no, case WHEN is_test = 0 then '否' else '是' end as '是否测试' from `tbl_order` WHERE `order_no` in ( 'afsd122112121' );