Oracle 10gR2 - RAMN Compressed backupset

It has been seen the size of compressed backupset is about 17.3% of
that of normal backupset from the following test.

In Lutz Hartmann's blog, it also stated that compression can reduce
the space needed to one-fifth.


Compressed
-----------

RMAN> backup incremental level 0
2> as compressed backupset database;
Starting backup at 23-SEP-2007 13:33:38
allocated channel: ORA_DISK_1
channel ORA_DISK_1: sid=127 devtype=DISK
channel ORA_DISK_1: starting compressed incremental level 0 datafile backupset
channel ORA_DISK_1: specifying datafile(s) in backupset
input datafile fno=00001 name=C:\ORACLEXE\APP\ORACLE\PRODUCT\10.2.0\ORADATA\ORCL\SYSTEM01.DBF
input datafile fno=00003 name=C:\ORACLEXE\APP\ORACLE\PRODUCT\10.2.0\ORADATA\ORCL\SYSAUX01.DBF
input datafile fno=00006 name=E:\ORADATA\ORCL\AUTO_TBS_DATA01.DBF
input datafile fno=00007 name=E:\ORADATA\ORCL\MANUAL_TBS_DATA01.DBF
input datafile fno=00002 name=C:\ORACLEXE\APP\ORACLE\PRODUCT\10.2.0\ORADATA\ORCL\UNDOTBS01.DBF
input datafile fno=00005 name=C:\ORACLEXE\APP\ORACLE\PRODUCT\10.2.0\ORADATA\ORCL\EXAMPLE01.DBF
input datafile fno=00004 name=C:\ORACLEXE\APP\ORACLE\PRODUCT\10.2.0\ORADATA\ORCL\USERS01.DBF
input datafile fno=00008 name=E:\ORADATA\ORCL\UNDO_DATCH01.DBF
channel ORA_DISK_1: starting piece 1 at 23-SEP-2007 13:33:43
channel ORA_DISK_1: finished piece 1 at 23-SEP-2007 13:37:08
piece handle=E:\ORAFLASH\ORCL\BACKUPSET\2007_09_23\O1_MF_NNND0_TAG20070923T133340_3HF8VSTC_.BKP tag=TAG20070923T133340 co
mment=NONE
channel ORA_DISK_1: backup set complete, elapsed time: 00:03:28
Finished backup at 23-SEP-2007 13:37:09

Starting Control File and SPFILE Autobackup at 23-SEP-2007 13:37:15
piece handle=E:\ORAFLASH\ORCL\AUTOBACKUP\2007_09_23\O1_MF_S_634052241_3HF92WXS_.BKP comment=NONE
Finished Control File and SPFILE Autobackup at 23-SEP-2007 13:37:45

RMAN> **end-of-file**

RMAN> exit


non-compressed
---------------

RMAN> backup incremental level 0 database;
Starting backup at 23-SEP-2007 13:42:39
using target database control file instead of recovery catalog
allocated channel: ORA_DISK_1
channel ORA_DISK_1: sid=128 devtype=DISK
channel ORA_DISK_1: starting incremental level 0 datafile backupset
channel ORA_DISK_1: specifying datafile(s) in backupset
input datafile fno=00001 name=C:\ORACLEXE\APP\ORACLE\PRODUCT\10.2.0\ORADATA\ORCL\SYSTEM01.DBF
input datafile fno=00003 name=C:\ORACLEXE\APP\ORACLE\PRODUCT\10.2.0\ORADATA\ORCL\SYSAUX01.DBF
input datafile fno=00006 name=E:\ORADATA\ORCL\AUTO_TBS_DATA01.DBF
input datafile fno=00007 name=E:\ORADATA\ORCL\MANUAL_TBS_DATA01.DBF
input datafile fno=00002 name=C:\ORACLEXE\APP\ORACLE\PRODUCT\10.2.0\ORADATA\ORCL\UNDOTBS01.DBF
input datafile fno=00005 name=C:\ORACLEXE\APP\ORACLE\PRODUCT\10.2.0\ORADATA\ORCL\EXAMPLE01.DBF
input datafile fno=00004 name=C:\ORACLEXE\APP\ORACLE\PRODUCT\10.2.0\ORADATA\ORCL\USERS01.DBF
input datafile fno=00008 name=E:\ORADATA\ORCL\UNDO_DATCH01.DBF
channel ORA_DISK_1: starting piece 1 at 23-SEP-2007 13:42:43
channel ORA_DISK_1: finished piece 1 at 23-SEP-2007 13:48:59
piece handle=E:\ORAFLASH\ORCL\BACKUPSET\2007_09_23\O1_MF_NNND0_TAG20070923T134241_3HF9DPPG_.BKP tag=TAG20070923T134241 co
mment=NONE
channel ORA_DISK_1: backup set complete, elapsed time: 00:06:17
Finished backup at 23-SEP-2007 13:48:59

Starting Control File and SPFILE Autobackup at 23-SEP-2007 13:49:00
piece handle=E:\ORAFLASH\ORCL\AUTOBACKUP\2007_09_23\O1_MF_S_634052940_3HF9RJ7B_.BKP comment=NONE
Finished Control File and SPFILE Autobackup at 23-SEP-2007 13:49:08


$ ls -lh
total 1.7G
-rwxrwx---+ 1 Administrators SYSTEM 265M Sep 23 13:37 O1_MF_NNND0_TAG20070923T133340_3HF8VSTC_.BKP
-rwxrwx---+ 1 Administrators SYSTEM 1.5G Sep 23 13:48 O1_MF_NNND0_TAG20070923T134241_3HF9DPPG_.BKP