高手救命啊～～～进来看看一个替换值的问题～～
update hyclub set rightNumber=0 where not exists(select * from hyclub where hynumber=rightNumber)
查询rightNumber，如果在hynumber里不存在，那么set rightNumber=0
这样写怎么错了？
[解决办法]
update hyclub set rightNumber=0 where hynumber <> rightNumber
[解决办法]
update a set rightNumber=0
from hyclub a
where not exists(select * from hyclub where hynumber=a.rightNumber)
[解决办法]
not exists(select * from hyclub where hynumber=rightNumber)
这样写,exists里面的与外面的没有连系.
要指定rightNumber 是外面的就对了..
[解决办法]
你的语句相当于
update a set rightNumber=0
from hyclub a
where not exists(select * from hyclub b where b.hynumber=b.rightNumber)
你要求的是：
update a set rightNumber=0
from hyclub a
where not exists(select * from hyclub b where b.hynumber=a.rightNumber)
[解决办法]
update hyclub set rightNumber=0 where not exists(select * from hyclub A where A.hynumber=rightNumber)
[解决办法]
update hyclub set rightNumber=0 from hyclub A where not exists
(select * from hyclub B B.hynumber=A.rightNumber)
[解决办法]
update a set rightNumber=0
from hyclub a
where not exists(select * from hyclub where hynumber=a.rightNumber)
和update hyclub set rightNumber=0 where hynumber <> rightNumber
是一样的查询结果，，，是同一个表，其实用后面的语句快些吧~~~
