sybase 怎样把两个虚拟的表左连接起来

Question

SQL语句如下：
select c.fund_account, c.stock_accounta, d.stock_account from (select a.fund_account, a.stock_account stock_accounta from tbaccountedit a where a.business_flag = 4020) c left outer join (select b.fund_account, b.stock_account stock_accountb from tbaccountedit b where b.business_flag = 4021) d on (c.fund_account = d.fund_account)执行为什么会报错。
急帖！！！

Answer 1

select c.fund_account, c.stock_accounta, d.stock_account 
from (
   select a.fund_account, a.stock_account stock_accounta //a.stock_account与stock_accounta之间掉了,
   from tbaccountedit a 
   where a.business_flag = 4020
) c left outer join 
(  select b.fund_account, b.stock_account stock_accountb //a.stock_account与stock_accounta之间掉了,
   from tbaccountedit b 
   where b.business_flag = 4021
) d on (c.fund_account = d.fund_account)