SQL重复记录查询和删除方法

时间:2021-08-03 23:55:25

MYSQL 查询和删除重复记录的方法很多,下面就为您介绍几种最常用的 MYSQL 查询和删除重复记录的方法,希望对您查询和删除重复数据方面能有所帮助。  SQL重复记录查询的几种方法:  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)  以上 SQL 记录重复数据查询和删除方法,希望能够帮助你。