Question

我已将问题简化为以下select语句。

select 
   u.UserId,
   aVariable = cast((case when exists(select * from TblUser u where u.Disabled=1) then 1 else 0 end) as bit), 
from TblUser u
where aVariable = 1

aVariable不是表的列，而只是在此select语句中获取值的列。

有没有办法在没有得到的情况下完成上述操作列名称无效aVariable错误？

Answer 1

select q.* from (
select 
   u.UserId,
   cast((case when exists(select * from TblUser u where u.Disabled=1) then 1 else 0 end) as bit) as aVar, 
from TblUser u
)q 
where q.aVar = 1

Answer 2

SELECT必须如此：

select 
   u.UserId,
   1 as aVariable
from TblUser u

Answer 3

你认为正确的陈述是没有意义的。

select q.* from (
select 
   u.UserId,
   cast((case when exists(select * from TblUser u where u.Disabled=1) then 1 else 0 end) as bit) as aVar, 
from TblUser u
)q 
where q.aVar = 1

上述声明表示如果有一个用户被禁用，请从tbluser中选择所有用户。

我认为您希望看到表中的用户被禁用。如果是这样，那么您需要以下select语句：

SELECT userid, disabled as aVar
FROM TblUser
WHERE disabled = 1

给这一点。

之前的回答被删除，因为这个问题有点不清楚。

Answer 4

你需要这样做：

select 
   u.UserId,
   aVariable = cast((case when exists(select * from TblUser u where u.Disabled=1) then 1 else 0 end) as bit), 
from TblUser u
where cast((case when exists(select * from TblUser u where u.Disabled=1) then 1 else 0 end) as bit) = 1

select-statement创建的列上的列名无效

4 个答案: