Renewing the Transaction Database

If the transaction database becomes corrupt, it may be necessary to delete and re-create it. At the Hub, this may be done using the ADMIN Module. However, at satellites it is not possible to delete and create databases directly.

Instead, the satellite transaction database must be renewed using the daemon. This may be done in one of the following ways:

• The RENEW DELETE <DB> command may be used. This is the preferred method of re-creating the transaction database file, as it works even when the database is too corrupt for the daemon to run. Note that <DB> must be the transaction database for the current location, as the command cannot be executed remotely.

  Following the command, ADMIN checks that all users are logged out and that the daemon has been shut down. Note that the check on the daemon takes up to 3 minutes. ADMIN then deletes the file for the transaction database (not its DB entry) and prompts the user to quit and to stop and re-start the daemon. When the daemon is restarted, it will automatically recreate the transaction database file.

• The RENEW <DB> AT <loc> command may be used to renew a transaction database remotely. Note that this command may fail, if the database corruption is severe and the daemon at <loc> cannot be started.

• If the transaction database file for a location is missing, the daemon will create a fresh version automatically when it is started up. This means that if for some reason the database is corrupt, the transaction database can still be renewed by deleting the corrupt version of the file manually. (Do not delete its definition in the Global database)

  After renewing, copy the location’s transaction database to all secondary locations (such as the Hub), using the RECOVER command. This will prevent reverse propagation when the database is synchronised at a secondary location.

  Note:
  The RENEW command may remove running commands because it deletes the transaction database.