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  • 查询及删除重复记录的SQL语句

    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)

     

     

    delete from 表名 where 字段ID in (select * from (select max(字段ID) from 表名 group by 重复的字段 having count(重复的字段) > 1) as b);

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  • 原文地址:https://www.cnblogs.com/helsing/p/5892315.html
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