The Danger in Backing Up the Online Transaction Journal

There is no danger in backing up the online transaction journal. The danger is in accidentally restoring it without fully intending the consequences. Consider the following situation in which restoring a backed up online transaction journal severely compromises recovery.

When a crisis is in progress, it is easy to make a simple mistake. One of the dangers that system administrators frequently encounter is during a database restore. When restoring the whole database, it is possible to also accidentally restore the backed up online transaction journal, thus overwriting the current online transaction journal with the older (and less complete) version of the journal file. This forces the system administrator to perform an incomplete recovery when the intention was to perform a complete recovery, thus losing the ability to recover valuable transactions.

When writing is switched to a new journal, the journal switched from is marked read-only, to prevent it from being accidentally copied over. The Restore Journals command in the JADE Database utility (jdbutil) or the restoreJournal command in the batch JADE Database utility (jdbutilb) will not overwrite an existing file. (For details, see Chapter 1.)