>sum(a.tvol)-NVL(sum(b.totcxlvol),000) as tvoladj;
>or
>NVL(sum(a.tvol)-sum(b.totcxlvol),sum(a.tvol) ) as tvoladj;
>
>Which syntax is better?
>
>I was wondering if the duplicate occurance of "sum(a.tvol)" was a performance killer.

Michael,

Without testing it I would go for the former. Less function calls are usually faster than more function calls.