drestore - restore a database


drestore [-uv] logfile


Drestore is used to restore one or more databases after a system crash. All databases logged by logfile are restored to their state just before the crash. This is necessary to restore the database to a consistent state.

Programs making a series of changes for one transaction often use transaction markers to denote the start and end of the transaction. Drestore knows about these markers and only restores completed transactions. Transactions that are incomplete are flagged, noted, and not restored.

The -u flag forces the restoration of all transactions - complete or not.

The -v flag produces output about the stages of drestore. Normally, drestore does its work silently. Errors about incomplete or inconsistent transactions are listed regardless of this flag. Using this flag helps to determine why a transaction is being flagged.

There is one other flag not listed in the usage message. This flag is intended only for debugging purposes. The -d flag produces output similar to plog(C-1) as drestore reads through the log file.



dlbegin(C-3), dlend(C-3), dlcancel(C-3).

C/Base Utilities Manual Chapter 5, Transaction Logging.


Backups and log files should be treated as a matched set. As new backups are done, a new log file should be started. If the log file does not match the backup, the before images stored in the log file won't match the current images and the associated record changes will be considered invalid.