>>Do you want to SUM for particular Client_Num or for (Clint_Num+Client_Src)?
>
>Clien_num + Client_src. It's the combination that makes a unique entity, since clients can have multiple funding sources.
>
>-Michelle

select 1 as dummy, * from tmpbal into cursor tmp ;
union all select -1 as dummy, * from pc ;
union all select 1 as dummy, * from pay

select client_num,client_src,SUM(dummy*amount) as balance ;
from tmp ;
group by 1,2