"datafile %s: incremental-start SCN equals checkpoint SCN"
*Cause: The incremental-start SCN which was specified when starting an
incremental datafile backup is equal to the
datafile's checkpoint SCN. Since an incremental backup can only
be applied to a datafile whose checkpoint SCN is between the
backup set incremental-start SCN (inclusive) and the backup set
checkpoint SCN (exclusive), there is no datafile that this backup
set could ever be applied to.
*Action: Specify a smaller incremental-start SCN.
NOTE that this message will usually only be encountered by the
user while taking an incremental backup with Recovery Manager.
Recovery Manager should intercept all usual cases of this error
and simply ignore the incremental backup for this file. So, if
you do encounter this error, please report it to Oracle Support.