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db1,db2ÊÇÒ»¸ö·þÎñÆ÷ server µÄ2¸öÊý¾Ý¿â
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T1:
id, name, T2id £¬discription
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id, subName
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select * from [aa] where a1 in (select max(a2),a1 from [aa] group by a1 )
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Table1£ºprimary key(a1)
a1(char) a2(int)
a 10
b & ......
ÈçÌ⣺select name from table1
µÃµ½½á¹û£ºname
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