我建库的时候但是没有注意字段的建立,数据已经有几百万了,有的数据需要重复,有的数据不能重复,不需要重复的一个表是部分关键字段重复的记录,比如haoma字段重复,而其他字段不一定重复或都重复可以忽略,现在不知道怎么处理,现在有一个语句,没有搞懂:
select identity(int,1,1) as autoID, * into #Tmp from tableName
select min(autoID) as autoID into #Tmp2 from #Tmp group by Name,autoID
select * from #Tmp where autoID in(select autoID from #tmp2)
select identity(int,1,1) as autoID, * into #Tmp from tableName
select min(autoID) as autoID into #Tmp2 from #Tmp group by Name,autoID
select * from #Tmp where autoID in(select autoID from #tmp2)
几百万,等等就好了。
delete from tab a where exists(select 1 from tab b where a.id=b.id and a.rowid>b.rowid);
我也觉得先把之前的帖子结了吧,不然观音姐姐会生气的。
hm,gsd,qh
aa,bb,cc
aa,bc,cc
aa,bc,cd
ab,dd,dc
就是要求hm字段唯一,其他有重复的,只保留一条数据,现在怎么处理,结果是:
hm,gsd,qh
aa,bb,cc
ab,dd,dc