Progress/400
Product Guide
Transaction Control
Transaction control, known as commitment control on the AS/400, is a mechanism that allows you to undo transactions and restore a database to its prior state. Commitment control protects you from writing incomplete changes to a database. Progress databases use a before-image file (.bi) to handle transaction control automatically, but Progress/400 does not.
The OS/400 handles commitment control automatically when you start journaling on a file. When an application opens database files with commitment control on, transactions can be applied or removed as transaction units. Each DB2/400 database file must have an active journal receiver for commitment control to be in effect. The journal receiver (*JRNRCV) is an OS/400 object that contains information about changes made to a DB2/400 physical file. The records of these changes are called journal entries. For information on starting and maintaining journaling, see the "Journaling" section.
The Progress/400 DataServer does not manage journal receivers or the journaling process, and it does not support Progress 2-phase commit.
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