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Restoring DatabasesLocate this document in the navigation structure

Use

After a database failure or database errors, you can restore a database or revert it to an earlier state by importing data backups and, if necessary, log backups from data carriers.

Prerequisites
  • You are logged on to the database as database system administrator or as a DBM operator with server authorization for restoring the database.

    More information: Glossary, Server Permission

  • The data carriers with the data backups and, where applicable, log backups are available.

    If you are using a tape loader, insert all tapes belonging to the backup.

    More information: Backing Up Data, Backing Up Log Entries

  • If you are using a third-party backup tool, connect it.

    More information: Installation Manual, Connecting Third-Party Backup Tools

  • The database is in the ADMIN operational state.

  • Only on Microsoft Windows:

    If you want to restore the database using backups from data carriers on a remote computer, carry out the steps described in Database Administration, Backing Up and Restoring Data with Remote Computers.

Procedure
  1. Select the database in the explorer tree.

  2. In the context menu of the database, choose Start of the navigation path Administration Tasks Next navigation step Recovery... End of the navigation path

  3. If necessary, transfer the database to the ADMIN operational state.

  4. Select the recovery type:

    Table 1: Recovery Types

    Recovery Type

    Description

    Additional Prerequisites

    Recover last backup

    You restore the last backup from the backup history

    The log files dbm.knl and dbm.mdf are not damaged. This means that the backup history is complete.

    If you are using third-party backup tools, then the dbm.ebf log file must also be not damaged.

    More information: Database Administration, Log Files

    Recover specified backup from history

    You restore a specific backup from the backup history

    The log files dbm.knl and dbm.mdf are not damaged. This means that the backup history is complete.

    If you are using third-party backup tools, then the dbm.ebf log file must also be not damaged.

    Recover a medium

    You restore the backup from a data carrier without referring to the backup history

    -

    Initialize database before recovery

    You initialize the database before restoring it

    Usually the database system attempts to import redo log entries still present in the log area during recovery. To prevent this and force the deletion of all redo log entries in the log area, initialize the log area before the recovery.

    Example

    After a training course, you want to restore the training course to its original state by importing a data backup with the original database state. By deleting the redo log entries, you ensure that all changes to the course database made by course participants are discarded.

    -

    Recover until a specific time

    You restore the database to its state at a particular point in the past

    If the desired point in time is after the last data backup and the log area no longer contains all the required redo log entries, for example because they were damaged, you also need the log backups since the last data backup.

  5. If necessary, select the backup template or data carrier.

  6. If necessary, select a backup.

  7. Start the recovery.

    The system displays the current status of the recovery process in the status window.

    The Recovery Results tab page shows the data carriers from which the system has already imported data or log entries.

    In the Actions view, the system displays the recovery steps performed so far.

    More information: Actions (View)

    Note

    If an error occurs during recovery, check whether your backup is intact.

    More information: Checking Backups

  8. Once the recovery is complete, choose Restart.

  9. If automatic log backup was active before the recovery, reactivate it now.

    More information: Activating or Deactivating Automatic Log Backup

  10. If necessary, recreate any damaged indexes.

    More information: Recreating Damaged Indexes

More Information

Database Administration, Restoring Databases