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如何去除my sql 数据表里一个字段的重复数据

如何去除my sql 数据表里一个字段的重复数据?中间用竖线分割开了,下附截图。
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吴孟桥 2016-06-12 13:07:32 2567 分享 版权
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  • 1、查找表中多余的重复记录,重复记录是根据单个字段(peopleId)来判断
    select * from people
    where peopleId in (select peopleId from people group by peopleId having count(peopleId) > 1)
    2、删除表中多余的重复记录,重复记录是根据单个字段(peopleId)来判断,只留有rowid最小的记录
    delete from people
    where peopleId in (select peopleId from people group by peopleId having count(peopleId) > 1)
    and rowid not in (select min(rowid) from people group by peopleId having count(peopleId )>1)
    3、查找表中多余的重复记录(多个字段)
    select * from vitae a
    where (a.peopleId,a.seq) in (select peopleId,seq from vitae group by peopleId,seq having count(*) > 1)
    4、删除表中多余的重复记录(多个字段),只留有rowid最小的记录
    delete from vitae a
    where (a.peopleId,a.seq) in (select peopleId,seq from vitae group by peopleId,seq having count(*) > 1)
    and rowid not in (select min(rowid) from vitae group by peopleId,seq having count(*)>1)
    5、查找表中多余的重复记录(多个字段),不包含rowid最小的记录
    select * from vitae a
    where (a.peopleId,a.seq) in (select peopleId,seq from vitae group by peopleId,seq having count(*) > 1)
    and rowid not in (select min(rowid) from vitae group by peopleId,seq having count(*)>1)

    2019-07-17 19:33:43
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