Oracle Incremental backup

Each data block in a datafile contains a system change number (SCN), which is the SCN at which the most recent change was made to the block. During an incremental backup, RMAN reads the SCN of each data block in the input file and compares it to the checkpoint SCN of the parent incremental backup. If the SCN in the input data block is greater than or equal to the checkpoint SCN of the parent, then RMAN copies the block.

A level 1 incremental backup can be either of the following types:

• A differential backup, which backs up all blocks changed after the most recent incremental backup at level 1 or 0
• A cumulative backup, which backs up all blocks changed after the most recent incremental backup at level 0

Incremental backups are differential by default.

Info about RMAN backup set.

prompt
prompt Available backup sets contained in the control file.
prompt Includes available and expired backup sets.
prompt 

SELECT
    bs.recid                                              bs_key
  , DECODE(backup_type
           , 'L', 'Archived Logs'
           , 'D', 'Datafile Full'
           , 'I', 'Incremental')                          backup_type
  , device_type                                           device_type
  , DECODE(   bs.controlfile_included
            , 'NO', null
            , bs.controlfile_included)                    controlfile_included
  , sp.spfile_included                                    spfile_included
  , bs.incremental_level                                  incremental_level
  , bs.pieces                                             pieces
  , TO_CHAR(bs.start_time, 'mm/dd/yy HH24:MI:SS')         start_time
  , TO_CHAR(bs.completion_time, 'mm/dd/yy HH24:MI:SS')    completion_time
  , bs.elapsed_seconds                                    elapsed_seconds
  , bp.tag                                                tag
  , bs.block_size                                         block_size
FROM
    v$backup_set                           bs
  , (select distinct
         set_stamp
       , set_count
       , tag
       , device_type
     from v$backup_piece
     where status in ('A', 'X'))           bp
 ,  (select distinct
         set_stamp
       , set_count
       , 'YES'     spfile_included
     from v$backup_spfile)                 sp
WHERE
      bs.set_stamp = bp.set_stamp
  AND bs.set_count = bp.set_count
  AND bs.set_stamp = sp.set_stamp (+)
  AND bs.set_count = sp.set_count (+)
ORDER BY
    bs.recid
/

Info about RMAN backup piece.

prompt
prompt Available backup pieces contained in the control file.
prompt Includes available and expired backup sets.
prompt 

SELECT
    bs.recid                                            bs_key
  , bp.piece#                                           piece#
  , bp.copy#                                            copy#
  , bp.recid                                            bp_key
  , DECODE(   status
            , 'A', 'Available'
            , 'D', 'Deleted'
            , 'X', 'Expired')                           status
  , handle                                              handle
  , TO_CHAR(bp.start_time, 'mm/dd/yy HH24:MI:SS')       start_time
  , TO_CHAR(bp.completion_time, 'mm/dd/yy HH24:MI:SS')  completion_time
  , bp.elapsed_seconds                                  elapsed_seconds
FROM
    v$backup_set    bs
  , v$backup_piece  bp
WHERE
      bs.set_stamp = bp.set_stamp
  AND bs.set_count = bp.set_count
  AND bp.status IN ('A', 'X')
ORDER BY
    bs.recid
  , piece#
/