SQL Server:几种查找和删除重复记录的方法

 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)