两表更新这样写有优化余地吗？

[yhd0411]

有两张表记录都约为200万条，进行更新操作，语句如下：

update infotemp set occurdate = '2011/04/07',bal = (select bal from tempnew a where infotemp.acno=a.acno) where exists  (select 1 from tempnew c where infotemp.acno = c.acno)

表索引是以acno为唯一字段

感觉执行了好长时间，有没有用其他方法更快一点？

[304的的哥]

update infotemp 
set occurdate = to_date('2011/04/07',yyyy/mm/dd)
    bal = (select bal from tempnew a where infotemp.acno=a.acno)
where exists  
      (select 1 from tempnew c where infotemp.acno = c.acno);

不知道，顶一下，等GS

[yhd0411]

看来没有希望了

[kingtiy]

update infotemp 
set occurdate = '2011/04/07',
bal =tempnew.bal
join tempnew 
on infotemp.acno = tempnew.acno

[kingtiy]

update infotemp 
set occurdate = '2011/04/07',
bal =tempnew.bal
from infotemp
join tempnew 
on infotemp.acno = tempnew.acno