Group by on Nested Query ??

Hi all!
Can anyone help me?
My problem is a group by!
For example

select tabA.x , tabB.y, (select sum(tabC.z)....) as q
.
.
.

group by tabA.x , tabB.y, q

I obtain an error!
What's wrong ??

Thanks a lot! Received on Mon Feb 12 2007 - 02:37:47 CST