-- @Discrepancy is a singleton from preceding select

IF @Discrepancy <= 0 AND @IsStatus = 0
   BEGIN
      UPDATE CBInvoice
      SET IsStatus = 1
         WHERE ...
END

Discrepancy (calculated as subtract a -(b+c), where a,b and c are fields in CBInvoice) and IsStatus are both fields in CBInvoice.


TIA