Journaling Extensions

Journaling records redundant copies of database update information to increase protection against loss of information due to hardware and software failure. GT.M provides the M commands ZTSTART and ZTCOMMIT, to mark the beginning and end of a logical transaction. When ZTSTART and ZTCOMMIT fence a logical transaction, which may consist of multiple global variable updates, journal records can assure recovery of incomplete application transactions.

The following table summarizes the GT.M language extensions for journaling.

Journaling Extensions




Extended to ensure that GT.M has transferred all updates to the journal file.


Marks the completion of a logical transaction.


Marks the beginning of a logical transaction.


Extended for examining journaling status.