VMS Help  —  RMU72  Set  Corrupt Pages
    Allows you to set pages, storage areas, and snapshot files
    as either corrupt or consistent in the corrupt page table
    (CPT). A corrupt page is one that contains meaningless data; an
    inconsistent page is one that contains old data (data that is not
    at the same transaction level as the database root file). Corrupt
    pages are logged to the CPT, which is maintained in the database
    root file. When the CPT becomes full (due to a large number of
    pages being logged), the area containing the most corrupt pages
    is marked as corrupt and the individual corrupt pages for that
    area are removed from the corrupt page table. The Oracle RMU Set
    Corrupt_Pages operation is an offline operation.

    If you reset a page or storage area in the CPT to consistent it
    does not remove any true corruption or inconsistencies. However,
    if you reset a snapshot file in the CPT to consistent, Oracle
    RMU initializes the snapshot file and thus removes any true
    corruption or inconsistency.

                                 CAUTION

       Use the RMU Set Corrupt_Pages command only after you
       fully understand the internal data structure and know the
       information the database should contain. Setting a page
       in a storage area that is truly corrupt or inconsistent to
       consistent does not remove the corruption or inconsistency.
       Setting truly corrupt or inconsistent pages in a storage
       area to consistent and continuing to access those pages can
       result in unrecoverable corruptions to the database.

       The RMU Restore and RMU Recover commands should be used
       first and should be part of your normal operating procedure.

                                   NOTE

       This command replaces two RdbALTER statements: MAKE
       CONSISTENT and UNCORRUPT. Both the RdbAlter statements,
       MAKE CONSISTENT and UNCORRUPT, are deprecated commands that
       may be removed in future versions.

    When a storage area is restored from backup files on a by-area
    basis, it does not reflect data that has been updated since
    the backup operation. The transaction level of the restored
    area reflects the transaction level of the backup file, not the
    transaction level of the database. Therefore, the transaction
    level of the restored area differs from that of the database.
    Oracle Rdb marks the area by setting a flag in the storage area
    file to inconsistent.

    You can perform a recovery by area to upgrade the transaction
    level of the restored area to that of the database. (After-
    image journaling must be enabled in order to restore by area.)
    If you are certain that no updates have been made to the database
    since the backup operation, you can use the RMU Set Corrupt_Pages
    command to change the setting of the flag from inconsistent to
    consistent.

    In addition, storage areas are corrupted by attempting an SQL
    rollback with one or more storage areas opened in batch-update
    transaction mode.

    The RMU Set Corrupt_Pages command allows you to access a database
    that is in an uncertain condition. Accordingly, the following
    message and question are displayed when you enter it to correct a
    corrupt or inconsistent storage area or storage area page. (This
    message is not displayed if you enter it to correct a corrupt or
    inconsistent snapshot file.)

                  ***** WARNING! *****

    Marking a storage area or page consistent does not
    remove the inconsistencies. Remove any inconsistencies
    or corruptions before you proceed with this action.

    Do you wish to continue? [N]
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