假設有表(UserTB)：
1、Union(不允許重復)
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SELECT *
FROM dbo.UserTB
WHERE deptId IN ( 1, 3 )
UNION
SELECT *
FROM dbo.UserTB
WHERE deptId IN ( 1, 2 )
結果：
2、Union All(允許重復)
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SELECT *
FROM dbo.UserTB
WHERE deptId IN ( 1, 3 )
UNION ALL
SELECT *
FROM dbo.UserTB
WHERE deptId IN ( 1, 2 )
結果：
