group by clause

 Hi,

     Lets say I have query like the following:

select x.*, y.id, sum(y.amount)

from x, y

where x.id = y.id 

group by x.*, y.id;

x.* in group by does not work. How to make it work? The table x has lot of columns so I have to use x.*.

Thanks a lot,

Arun