凌晨!求一句SQL
有三个表 
 TA 
 ____________ 
 UserID      Type 
 1                      "A1 " 
 1                      "A2 " 
 2                      "A1 " 
 1                      "A2 " 
 2                      "A1 " 
 1                      "A2 " 
 1                      "A1 "   
 我想统计用户1拥有的纪录中A1,A2的个数,所以写 
 SELECT   SUM(IIF(Type= "A1 ",1,0)   AS   A1,SUM(IIF(Type= "A2 ",1,0)   AS   A1   WHERE   UserID=1 
 这句话是完全没有问题的。   
 另外一张表 
 TU 
 ---------- 
 UserID            Point 
 1                           1000 
 2                           1500   
 我想取出用户1的point,写SELECT   Point   WHERE   UserID=1 
 这句话也没有问题   
 我想把这两句话合并到一句SQL中,请问我改怎么做?   
 我这样 
 SELECT   SUM(TU.Point)   AS   Point,SUM(IIF(TA.Type= "A1 ",1,0)   AS   A1,SUM(IIF(TA.Type= "A2 ",1,0)   AS   A1,SUM(1)   AS   [Time]   FROM   TA,TU   WHERE   TA.UserID   AND   TB.UserID   
 这样我用Point/Time也能得到正确的Point   
 但是问题出来了,如果TA里没有用户1的纪录,这个查询将什么也不返回,但是我希望,他能返回Point,TA如果没有纪录,就返回0   
    请问,这条语句该怎样写?谢谢   
------解决方案----------------------用子查询处理   
 SELECT  
     (select SUM([Point]) from TU where [UserID]=T.[UserID] ) AS Point,  
     SUM(IIf([Type]= "A1 ",1,0)) AS A1,  
     SUM(IIf([Type]= "A2 ",1,0)) AS A2 
 FROM TA as T 
 WHERE [UserID]=1