Question

我使用以下mysql查询，

DELIMITER $$
DROP PROCEDURE IF EXISTS `allied`.`aboutus_delete`$$
CREATE DEFINER=`allied`@`%` PROCEDURE `aboutus_delete`(
IN p_Id int(11)
)
BEGIN
   if exists(   select aboutUsId 
                  from aboutus 
                 where aboutUsId=p_id 
                   and isDeleted=0
            )
      update aboutus set isDeleted=1 where aboutUsId=p_id
   else
      select 'No record to delete'
END$$
DELIMITER ;

但是当我执行它时我得到了这个错误......

Error Code : 1064
You have an error in your SQL syntax; check the manual that corresponds 
to your MySQL server version for the right syntax to use near 
'update aboutus set isDeleted=1 where aboutUsId=p_id
else
   select 'No record to' at line 6

修改

使用分号似乎不起作用，

if exists(select aboutUsId from aboutus where aboutUsId=p_id and 
 isDeleted=0) then
   update aboutus set isDeleted=1 where aboutUsId=p_id;
else
   select 'No record to delete';

Answer 1

这是一个不同的问题：您可以稍微优化此过程。为什么一个查询会执行两次数据存储？只需将isDeleted属性设置为1，然后检查row_count值。

BEGIN
  UPDATE aboutus SET isDeleted = 1 WHERE aboutUsId = p_id AND isDeleted = 0;
  IF (SELECT row_count()) <= 0 THEN
    SELECT 'No record to delete';
  END IF;
END

Answer 2

你错过了'IF'中的'THEN'......

Answer 3

除了分号和THEN之外，您还缺少END IF来终止IF语句。

mysql查询有什么问题？

3 个答案: