mysql查询重复数据

Posted 2021-01-15 LDDXFS

表全部数据

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1 查询people_no重复的记录

select * from people
where people_no in (select   people_no from   people group by   people_no having count(people_no) > 1);

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2 查询people_no重复的记录 ，排除最小id，如果删除改为delete from

select * from people
where people_no in (select   people_no from people group by   people_no   having count(people_no) > 1) and  
id not in (select min(id) from   people group by people_no having count(people_no)>1);

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3 查询people_no people_name重复的记录

select * from people a
where (a.people_no,a.people_name) in (select people_no,people_name from people GROUP BY people_no,people_name HAVING count(*)>1);

 

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4 查询people_no people_name重复的记录，排除最小id

select * from people a
where (a.people_no,a.people_name) in (select people_no,people_name from people GROUP BY people_no,people_name HAVING count(*)>1) and
a.id not in    (select min(id) from people GROUP BY people_no,people_name HAVING count(*)>1);