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sql 显示重复数据

select id from A
where id in (select id from A group by id having count(1) >= 2)

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select id,count(1) 重复次数 from A group by id having count(1)>1;
查询出来的结果都是id重复的，重复次数 中的数值就是重复了多少次。

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  sql  去重复  distinct

select distinct name from A

去重复的name

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