MSSQL取得或删除重复数据

1.取得不重复的数据

select * from Persons where Id in
(
SELECT    MAX(Id) AS Expr1
FROM    Persons
GROUP BY Name, Gender
)

2.删除重复的数据【MAX换成MIN会有不同的效果】

delete from Persons
where Id not in
(
SELECT    MAX(Id) AS Expr1
FROM    Persons
GROUP BY Name, Gender
)
时间: 2024-12-19 06:24:26

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