Buen día David,
Complementando el código que nos comparte Marco:
DECLARE @DEUDA INT
SET @DEUDA = (SELECTSUM(DocTotal-PaidToDate)
FROM OINV
WHERE DocDueDate <= (GETDATE()-1) AND Series != '41' )
SELECTDISTINCT'TRUE'FROM OINV WHERE @DEUDA > 0
Saludos,