In systems that use sequential master files, the order of the
transaction records in the batch is critical to correct and complete processing. As
the batch moves through the process, it must be re-sorted in the order of the master
file used in each run. An out-of-sequence sales order record in a batch may prevent the
remaining downstream records from being processed. A more serious problem can occur
when the sequencing error is not detected and the downstream records are processed
against the wrong customer accounts. A sequence check control should be in place to
compare the sequence of each record in the batch with the previous record to ensure
that proper sorting took place. Out-of-sequence records should be rejected and resubmitted
for subsequent processing to allow the other records in the batch to be properly
processed