给没有它,您将收到
Msg 156, Level 15, State 1, Line 21
Incorrect syntax near the keyword 'WHERE'.
试试这个(给别名)
DECLARE @TableA Table(A int, B int)
DECLARE @TableB Table(A int, B int)
INSERT INTO @TableA VALUES(1,1)
INSERT INTO @TableA VALUES(1,2)
INSERT INTO @TableA VALUES(1,3)
INSERT INTO @TableA VALUES(1,4)
INSERT INTO @TableB VALUES(2,1)
INSERT INTO @TableB VALUES(2,2)
INSERT INTO @TableB VALUES(2,3)
INSERT INTO @TableB VALUES(2,4)
SELECT A
FROM
(
SELECT A, B FROM @TableA
UNION
SELECT A, B FROM @TableB
)X -- here X is table Alias
WHERE B > 0
结果
一个别名
1
1
1
1
2
2
2
2
是的,它是可能的。有什么问题吗? – hims056
我收到错误'关键字'WHERE'附近的错误语法。'并且无法运行查询。 – BlargleMonster
缺少别名name..check提供的答案 –