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±í1 user (Óû§ÐÅÏ¢ )
username password
A 123
B 000
C 555
±í2 record (Óû§¼Ç¼)
id username logintime
1 C 2009-10-10
2 A 2009-10-11
3 A 2009-10-12
4 B 2009-10-13
5 B 2009-10-15
6 C 2009-10-16
±í2 idÁÐÊÇ×Ô¶¯±àºÅ£¬recordtimeÊÇ×îºóµÇ½ʱ¼äʱ¼ä£¬ÏÖÔÚÒªÏÔʾ±í1µÄËùÓÐÐÅÏ¢ ¼°×îºó¼Ç¼ʱ¼ä,½á¹ûÓ¦¸ÃÈçÏÂ
username password logintime
A 123 2009-10-12
B 000 2009-10-15
C 555 2009-10-16
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select username,password,(select top 1 logintime from record where record.username=[user].username order by logintime desc ) from [user]
select a.*,b.lasttime from user as a
left join
(select max(logintime)as lasttime,username from record group by username)
as b
on a.username = b.username
select t1.*,t2.lasttime from user t1
left join
(select username,max(logintime)as lasttime from record g
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date(Ö÷) outid(Ö÷) inid(Ö÷) num amt
2009 1 2 1 500 Ϊ 1 µ¥Î» ÔÚ2009Ä ......
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×Ö¶Î1,×Ö¶Î2.....×Ö¶ÎN,Status,ParentID
1,Name1....test1,1,99
1,Name1....test1,3,99
1,Name2....test2,1,101
1,Name2....test2,3,101
1,Name3....test3,2,101
1,Name1....test1,4,101
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1,Na ......