>>Without seek before select SUM I got the following results
>>Found a mismatch on I801972COL cRate = 0 laArr[1]= 0.100000000
>>Found a mismatch on I518767COL cRate = 0 laArr[1]= 0.100000000
>>
>>The first invoice has a different person as a salesman, and the second doesn't exist in Comision at all (I just tried in Command window to search for these invoices).
>
>The two commands may well leave the record pointer in different places.
>
>Tamar

That's true, but here is the exact code

SELECT Comision
				lnRecno = RECNO()
                SET ORDER TO com_inv IN comision
                
                SELECT SUM(rate*SHARE/10000) AS crate WHERE inv_no+salesman = m.ccinv + m.Slsman ;
                	FROM comision INTO ARRAY laArr
                lcRate = EVL(laArr[1],0)		
                IF SEEK(m.ccinv + m.Slsman)                	
					SUM (rate*SHARE/10000) TO cRate WHILE inv_no+salesman = m.ccinv + m.Slsman
				ELSE
					cRate = 0
				endif		
                	
                	IF NOT m.cRate == m.lcRate
                		=MESSAGEBOX("Found a mismatch on " + m.ccinv + m.Slsman)
                		_cliptext = _cliptext + "Found a mismatch on " + m.ccinv + m.Slsman + " cRate = " + ;
                		         	TRANSFORM(m.cRate)  + " laArr[1]= " + TRANSFORM(m.lcRate)
                	ENDIF

The two reported mismtach cases are wrong, since in first case the invoice is for different person and in second it doesn't exist. I just re-indexed the table on inv_no + salesman and the problem persists.

Do you know, what I'm doing wrong?

Thanks again.