Syntax option:

       INCREMENTAL BACKUP SCAN OPTIMIZATION
       NO INCREMENTAL BACKUP SCAN OPTIMIZATION

 Specifies whether Oracle Rdb checks each area's SPAM pages or each
 database page to find changes during incremental backup.

    If you specify INCREMENTAL BACKUP SCAN OPTIMIZATION, Oracle Rdb
    checks each area's SPAM pages and scans the SPAM interval of
    pages only if the SPAM transaction number (TSN) is higher than
    the root file backup TSN, which indicates that a page in the SPAM
    interval has been updated since the last full backup operation.
    Updates in the SPAM interval result in an extra I/O.

    Specify INCREMENTAL BACKUP SCAN OPTIMIZATION if your database has
    large SPAM intervals or infrequently occurring updates, and you
    want to increase the speed of incremental backups.

    If you specify NO INCREMENTAL BACKUP SCAN OPTIMIZATION, Oracle
    Rdb checks each page to find changes during incremental backup.

    Specify the NO INCREMENTAL BACKUP SCAN OPTIMIZATION clause if
    your database has frequently occurring updates, uses bulk-load
    operations, or does not use incremental backups, or if you want
    to improve run-time performance.

    The default is INCREMENTAL BACKUP SCAN OPTIMIZATION.