Scan_Optimization
    Noscan_Optimization

    Specifies whether or not RMU Backup should employ scan
    optimizations during incremental backup operations.

    By default, RMU Backup optimizes incremental backup operations
    by scanning regions of the database that have been updated since
    the last full backup operation. The identity of these regions
    is stored in the database. Only these regions need to be scanned
    for updates during an incremental backup operation. This provides
    a substantial performance improvement when database activity is
    sufficiently low.

    However, there is a cost in recording this information in the
    database. In some circumstances the cost might be too high,
    particularly if you do not intend to use incremental backup
    operations.

    The Scan_Optimization qualifier has different effects, depending
    on the type of backup operation you perform. In brief, you can
    enable or disable the scan optimization setting only when you
    issue a full offline backup command, and you can specify whether
    to use the data produced by a scan optimization only when you
    issue an incremental backup command. The following list describes
    this behavior in more detail:

    o  During an offline full backup operation, you can enable or
       disable the scan optimization setting.

       Specify the Scan_Optimization qualifier to enable recording
       of the identities of areas that change after this backup
       operation completes.

       Specify the Noscan_Optimization qualifier to disable recording
       of the identities of areas that change after this backup
       operation completes.

       By default, the recording state remains unchanged (from the
       state it was in prior to execution of the Backup command)
       during a full backup operation.

       Note that specifying the Scan_Optimization or Noscan_
       Optimization qualifier with an offline full backup operation
       has no effect on the backup operation itself, it merely allows
       you to change the recording state for scan optimization.

    o  During an online full backup operation, the qualifier is
       ignored.

       The recording state for scan optimization remains unchanged
       (from the state it was in prior to execution of the Backup
       command). If you execute an online full backup operation
       and specify the Scan_Optimization or Noscan_Optimization
       qualifier, RMU Backup returns an informational message to
       indicate that the qualifier is being ignored.

    o  During an incremental backup operation, the qualifier directs
       whether the scan optimization data (if recorded previously)
       will be used during the operation.

       If you specify the Scan_Optimization qualifier, RMU Backup
       uses the optimization if Oracle Rdb has been recording the
       regions updated since the last full backup operation.

       If you specify the Noscan_Optimization qualifier, RMU Backup
       does not use the optimization, regardless of whether Oracle
       Rdb has been recording the identity of the regions updated
       since the last full backup operation.

       You cannot enable or disable the setting for scan
       optimizations during an incremental backup operation.

       By default, the Scan_Optimization qualifier is used during
       incremental backup operations.