如何删除同一个表中的重复记录，只有3个字段重复。但不是全部删除掉。的留下一条把

谢谢
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参照
http://expert.csdn.net/Expert/topic/431/431723.xml?temp=.1738245
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select into #tmp distinct col1 from table
delete from table t join #tmp tm on t.col1<>tm.col1
delete from #tmp

select into #tmp distinct col2 from table
delete from table t join #tmp tm on t.col2<>tm.col2
delete from #tmp

select into #tmp distinct col3 from table
delete from table t join #tmp tm on t.col3<>tm.col3

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先用distinct把唯一的数据插入临时表，然后删除旧表数据，再把临时表的数据写回去。

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selcet min(重复字段1)，min(重复字段2)，min(重复字段3)，别的字段
into new table
from talbe

new table 就是你要的表

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select identity(int,1,1),* into #tmp from yourtable

delete from #tmp where x not in (select max(x) from #tmp group by a,b,c )

truncate yourtable

insert yourtable select (除x以外的字段） from #tmp