?????求一sql语句:删除a表中满足条件X而且存在于表b中的记录?????
(a,b两表表结构一样,关联条件是Y) 
 大致是下面的意思: 
 delete   a   where   X 
 and   exists(select   *   from   a,b   where   Y) 
 求助???!!!
------解决方案--------------------delete a  from a  where X 
 and exists(select * from b where b.col1?a.col) 
------解决方案--------------------  Delete A From A 
 Where X 
 And Exists(Select * From B Where Y)
------解决方案--------------------delete a 
 from a inner join b on Y  
 where x