SQL语句删除重复数据

1.如表中没有主键，先添加自动增长主键

alter table 表名 add 列名 int identity (1,1) primary key

2.删除重复数据

delete from 表名 where id not in
(select min(id) from 表名 group by id)

时间： 2025-01-18 12:58:07

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