better interface for queries?

Hello

Is there any possibilities to improve  the interface for queries,
I   just have   in  mind  very  simple commands   like adding and
multiplying columns.   While in scal  there  is a interface which
helps me to do this in the  query I had more  or less to do trial
and error to find out field1+field2 works, any kind of interface,
in the line of the scal interface,  would be very helpful. But is
this difficult to implement?

Uwe Brauer