Daniel:

>>>>
select customer, sum(invoices) from ;
(select Customer, count(InvNum) as Invoices;
from ActiveInvoices;
group by Customer;
union select Customer, count(InvNum) as Invoices;
from HistInvoices;
group by Customer;
order by Customer)
group by customer
>>>>

This does not work because the UNION clause does not work in subqueries...

I don't know of any way to do this in one pass but this works:

Select Customer, count(*) As ActInv, 0 As HisInv ;
   From ActiveInvoices ;
   Group By Customer ;
Union Select Customer, 0 As ActInv, Count(*) As HisInv ;
   From HistInvoices ;
   Group By Customer ;
Into Cursor TotInv

Select Customer, Sum(ActInv + HistInv) As InvCount ;
   From TotInv ;
   Group By Customer


Daniel