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My sql 中删除表中重复记录只保留一条
在几千条记录里,存在着些相同的记录,如何能用SQL语句,删除掉重复的呢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 peopleName in (select peopleName from people group by peopleName having count(peopleName) 》 1) and peopleId not in (select min(peopleId) from people group by peopleName having count(peopleName)》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) 6.消除一个字段的左边的第一位：update tableName set )-1)) where Title like ’村%’7.消除一个字段的右边的第一位：update tableName set )-1)) where Title like ’%村’8.假删除表中多余的重复记录（多个字段），不包含rowid最小的记录 update vitae set ispass=-1where peopleId in (select peopleId from vitae group by peopleId
SQL中删除重复数据并保留一个求语句！！！
1、建立临时表，将重复记录查询出来用distinct去重插入到临时表2、删除实表中的重复记录3、将临时表中的记录插入到实表
SQL检索，但检索结果中有某字段内容重复的数据只保留1条显示
--判断一个字段重复就只显示一条，用distinct是不行的，可以用row_number()根据这个字段分组显示优先级，然后只取每个组的第一条select * from(select *,row_number() over(partition by 判断重复的字段名) as f_id from 表名) twhere f_id =1
