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.
