Sql去重及查询重复

1、最简单的是使用distinct，去除所有查询字段信息一样的数据

    

---------------------------------------以下为有主键的情况下使用

2、 查询，去重，保留最小id信息
select * from people where id in (
    select MIN(id) from people group by name,sex)

 

 

3、 查询全部的重复信息
select * from people where id not in (

    select min(id) from people group by name,sex HAVING COUNT(*) < 2)

 

4、查询多余的重复信息
select * from people where id not in (

    select MIN(id) from people group by name,sex)

 

5、删除多余重复的信息，只保留最小ID
delete from people where id not in(
    select MIN(id) from people group by name,sex
)