请问
表1:结构如下
pkid skuid locid cntqty
1 123 c001 2
2 123 c001 3
3 234 c002 4
4 234 c002 4
5 123 c001 1
现在需要保留重复数据(skuid+locid相等即为重复)中cntqty 值较大的一个,如何操作呢?谢谢
------解决方案--------------------
delete from tablename where not exists (select top 1 * from tablename group by locid,skuid order by cntqty desc,pkid desc)
------解决方案--------------------
declare @ta table(pkid int, skuid int, locid varchar(4), cntqty int)
insert @ta
select 1, 123, 'c001 ', 2
union all select 2, 123, 'c001 ', 3
union all select 3, 234, 'c002 ', 4
union all select 4, 234, 'c002 ', 4
union all select 5, 123, 'c001 ', 1
delete a from @ta a where pkid not in
(select top 1 pkid from @ta where skuid=a.skuid and locid =a.locid order by cntqty desc )
select *from @ta
（所影响的行数为 5 行）
（所影响的行数为 3 行）
pkid skuid locid cntqty
----------- ----------- ----- -----------
2 123 c001 3
4 234 c002 4
（所影响的行数为 2 行）