SQL语句删除表中重复字段

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)
  
比方说在A表中存在一个字段“name”,而且不同记录之间的“name”值有可能会相同,
  现在就是需要查询出在该表中的各记录之间,“name”值存在重复的项;
  Select Name,Count(*) From A Group By Name Having Count(*) > 1

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