用SQL語句,刪除掉重複的記錄

1、查找表中多餘的重複記錄,重複記錄是根據單個字段(peopleId)來判斷
select * from people
where peopleId in (select peopleId from people group by peopleId having count(peopleId) > 1)
2、刪除表中多餘的重複記錄,重複記錄是根據單個字段(peopleId)來判斷,只留有rowid最小的記錄
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、查找表中多餘的重複記錄(多個字段)
select * from vitae a
where (a.peopleId,a.seq) in (select peopleId,seq from vitae group by peopleId,seq having count() > 1)
4、刪除表中多餘的重複記錄(多個字段),只留有rowid最小的記錄
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、查找表中多餘的重複記錄(多個字段),不包含rowid最小的記錄
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)
比方說在A表中存在一個字段“name”,而且不同記錄之間的“name”值有可能會相同,
現在就是需要查詢出在該表中的各記錄之間,“name”值存在重複的項;
Select Name,Count(
) From A Group By Name Having Count() > 1
如果還查性別也相同大則如下:
Select Name,sex,Count(
) From A Group By Name,sex Having Count(*) > 1

ps:篩選出指定月,指定日,指定年的方法:

 SELECT * FROM dbo.v_CashmereInBodyDetails WHERE YEAR(c_time)='2010' AND MONTH(c_time)=6 AND DAY(c_time)=8

 篩選出2010年6月8日的數據
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