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  • sql 删除重复行

    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)
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  • 原文地址:https://www.cnblogs.com/gongyu/p/3871573.html
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