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Journal Record Entries

Log Changes in Records

CA IDMS/DB uses journal record entries to log changes to the records in a database. A journal record entry is an image of a database record. As a database record is added, deleted, or modified, CA IDMS/DB writes a before image that contains the image of the record before update and an after image that contains the image of the record after update.

Journal Images For Modified Records

On a change to an existing record, the contents of before and after images are dependent on how the processing of the DML statement affects the database record:

Affect on Database Record

Contents of Journal Record Entry

Data in the record changes

  • Database key of the record occurrence
  • Prefix portion of the record occurrence
  • Data portion of the record occurrence

Record's relationships in a set changes

  • Database key of the record occurrence
  • Prefix portion of the record occurrence

Journal Images For New or Deleted Records

If a DML statement adds a new record occurrence into the database, the before image of the record is null. Similarly, if a DML statement removes a record occurrence, the after image of the record is null.