ÇóÒ»ÌõSQL[Access]

±í½á¹¹´óÖÂÈçÏÂ:
A
loginid        reid        date
zhangsan        84          2010-1-3 23:50:07
lisi            84          2010-1-3 21:56:35
wangwu          84          2010-1-3 16:18:43
aaa            75          2009-12-19 8:19:18
bbb            77          2009-11-27 8:16:42

ÎÒÆÚÍû³öÀ´ÕâÑùµÄ½á¹û¼¯
loginid        reid        date
zhangsan        84          2010-1-3 23:50:07
aaa            75          2009-12-19 8:19:18
bbb            77          2009-11-27 8:16:42

Ò²¾ÍÊÇͬһÌõ¼Ç¼(reid)ֻȡ×î½üµÄÈÕÆÚ

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Select Loginid,reid,max(date) as date from a group by  Loginid,reid

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ßÀ£¬¼ÙÉè±íÖÐÓÐΨһÐÍ×ֶΠID£¬ÄÇô¾Í

select * from A b where ID in (select top 1 ID from A where reid=b.reid order by [date] desc)

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select * from A b where [date] in (sel