sql刪除重複資料
如果該錶需要刪除重複的記錄(重覆記錄保留1條),可以按以下方法刪除
select distinct * into #tmp from tablename
drop table tablename
select * into tablename from #tmp
drop table #tmp
另一種方法是乙個字段重複,id不重複
delete 表 where id not in(
select max(id) as id from 表 group by rows) --- 刪除重複行
select * from 表 where id in(
select max(id) as id from 表 group by rows) --重複行只查詢一條
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