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update orders_father set ostatus=5,ofintimesys=now() where oid =
(select oid from
(SELECT oid FROM orders_father where TIMESTAMPDIFF(HOUR,odlvtime,now())>parameter and ostatus=4)
as tempTable)
;
这是代码1。
update orders_father set ostatus=5,ofintimesys=now() where oid =any
(select oid from
(SELECT oid FROM orders_father where TIMESTAMPDIFF(HOUR,odlvtime,now())>parameter and ostatus=4)
as tempTable)
;
这是代码2,在oid=后面增加了any
我的疑问是,为何代码1会出现Error Code: 1242. Subquery returns more than 1 row
这种错误,而代码2不会? 谢谢各位大神
背景:我是在存储过程中使用的...
黄舟2017-04-17 15:31:52
where xxx = yyy
的时候,右边必须是单一的值,不能是多个值,而你第一个语句里面的
(SELECT oid FROM orders_father where TIMESTAMPDIFF(HOUR,odlvtime,now())>parameter and ostatus=4)
as tempTable)
会查出多个值,所以报Error Code: 1242. Subquery returns more than 1 row
的错误
解决的方法就是把where xxx = yyy
变成where xxx in(yyy)
或者where xxx = any yyy
,这两个表达是一个意思,不过any还可以其他的比较,比如where xxx > any yyy