Oracle® Database Backup and Recovery Reference 11g Release 2 (11.2) E10643-07 |
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PDF · Mobi · ePub |
Use the DELETE
command to perform the following actions:
Delete physical backups and copies.
Update the repository records in the target control file to show that the files are deleted. For example, the record for a backup piece in V$BACKUP_PIECE.STATUS
shows the value D
.
Remove the repository records for deleted files from the recovery catalog (if you use a catalog). For example, RC_BACKUP_PIECE
no longer contains a row for a deleted backup piece.
RMAN must be connected to a target database, which must be mounted or open.
RMAN uses all configured channels to perform the deletion. If you use DELETE
for files on devices that are not configured for automatic channels, then you must use ALLOCATE CHANNEL FOR MAINTENANCE
. For example, if you made a backup with an SBT channel, but only a disk channel is configured, then you must manually allocate an SBT channel for DELETE
. An automatic or manually allocated maintenance channel is required when you use DELETE
on a disk-only file.
The best practice is to run CROSSCHECK
to update the status of backups and copies in the repository and then run DELETE
to remove the desired files. When running RMAN interactively, DELETE
displays a list of files and prompts for confirmation before deleting any file in the list. If you confirm, then RMAN shows each item as it is deleted. When reading commands from a command file, RMAN does not prompt for confirmation.
You can view the status of backups and copies recorded in the RMAN repository through LIST
, V$
views, or recovery catalog views (if you use a catalog). The repository record for a backup can fail to reflect its physical status. For example, a user deletes a disk backup with the Linux rm
command. The backup record cannot be updated by rm
, so the RMAN repository shows the file as available although it no longer exists.
Behavior of DELETE Command for Files of Different Status Values
Table 2-5 describes the behavior of DELETE
when the FORCE
option is not specified.
Table 2-5 Behavior of DELETE Command Without FORCE Option
Repository Status | Physical Status | Behavior of DELETE Command |
---|---|---|
Not found on media |
Does not delete the object and reports the list of mismatched objects after the job. RMAN does not update the repository status. |
|
Found on media |
Does not delete the object and reports the list of mismatched objects after the job. RMAN does not update the repository status. |
|
Any |
Removes repository record and deletes object if it exists. All I/O errors are ignored. |
Backup Deletion in a Data Guard Environment
"RMAN Backups in a Data Guard Environment" explains the difference between the association and accessibility of a backup. In a Data Guard environment, the database that creates a backup or copy is associated with the file. You can use maintenance commands such as CHANGE
, DELETE
, and CROSSCHECK
for backups when connected to any database in the Data Guard environment if the backups are accessible. In general, RMAN considers tape backups created on any database as accessible to all databases in the environment, whereas disk backups are accessible only to the database that created them.
If a deletion is successful, then RMAN removes the metadata for the file, even if the file is associated with another database. If a deletion was not successful, and if the file is associated with another database in the Data Guard environment, then RMAN prompts you to perform the same DELETE
command while connected as TARGET
to the database associated with the file. You must use DELETE ... FORCE
to delete the file metadata.
(maintSpec::=, obsOperandList::=, deviceSpecifier::=)
maintSpec::=
(listObjList::=, archivelogRecordSpecifier::=, maintQualifier::=, deviceSpecifier::=, recordSpec::=)
Syntax Element | Description |
---|---|
FORCE |
Deletes specified files—whether or not they exist on the media—and removes repository records (see Example 2-68).
RMAN ignores any I/O errors for the deleted objects. RMAN also ignores any |
NOPROMPT |
Deletes specified files without first listing the files or prompting for confirmation. The DELETE NOPROMPT command displays each item as it is deleted. |
EXPIRED |
Removes only files whose status in the repository is EXPIRED (see Example 2-65). RMAN marks backups and copies as expired when you run a CROSSCHECK command and the files are absent or inaccessible. To determine which files are expired, run a LIST EXPIRED command.
If for some reason a backup marked |
maintSpec |
Deletes backups and copies.
You can set rules for the deletion with the Note: See Also: |
forDbUniqueNameOption |
Deletes the backups and copies in maintSpec that are exclusively associated with the specified DB_UNIQUE_NAME in a Data Guard environment.
Note: The If RMAN successfully deletes tape backups associated with the specified Note: You cannot use See Also: |
OBSOLETE |
Deletes data file backups and copies recorded in the RMAN repository that are obsolete, that is, no longer needed (see Example 2-66). RMAN also deletes obsolete archived redo log files and log backups.
RMAN determines which backups and copies of data files are no longer needed, which in turn determines when logs (and backups of logs) are no longer needed. RMAN considers the creation of a data file as a backup when deciding which logs to keep. RMAN first uses the options specified with Note: Note: If you make a backup with the |
obsOperandList |
Specifies the criteria for determining which backups and copies are obsolete.
See Also: |
DEVICE TYPE deviceSpecifier |
Restricts the deletion to obsolete backups and copies created on the specified device type only.
See Also: |
Example 2-65 Deleting Expired Backups
This example uses a configured sbt
channel to check the media manager for expired backups of the tablespace users
that are more than one month old and removes their recovery catalog records.
CROSSCHECK BACKUPSET OF TABLESPACE users DEVICE TYPE sbt COMPLETED BEFORE 'SYSDATE-31'; DELETE NOPROMPT EXPIRED BACKUPSET OF TABLESPACE users DEVICE TYPE sbt COMPLETED BEFORE 'SYSDATE-31';
Example 2-66 Deleting Obsolete Backups
This example deletes backups and copies that are not needed to recover the database to an arbitrary SCN within the last week. RMAN also deletes archived redo log files that are no longer needed.
DELETE NOPROMPT OBSOLETE RECOVERY WINDOW OF 7 DAYS;
Example 2-67 Deleting Archived Redo Log Files That Have Been Backed Up
Assume that you have configured RMAN settings as follows:
CONFIGURE DEFAULT DEVICE TYPE TO sbt; CONFIGURE ARCHIVELOG DELETION POLICY TO BACKED UP 2 TIMES TO DEVICE TYPE sbt;
The following DELETE
command deletes all archived redo log files on disk if they are not needed to meet the configured deletion policy, which specifies that logs must be backed up twice to tape (sample output included):
RMAN> DELETE ARCHIVELOG ALL; allocated channel: ORA_DISK_1 channel ORA_DISK_1: SID=84 device type=DISK List of Archived Log Copies for database with db_unique_name PROD ===================================================================== Key Thrd Seq S Low Time ------- ---- ------- - --------- 107 1 4 A 12-FEB-07 Name: /orcva/PROD/archivelog/2007_02_12/o1_mf_1_4_2x28bpcm_.arc 108 1 5 A 12-FEB-07 Name: /orcva/PROD/archivelog/2007_02_12/o1_mf_1_5_2x28g7s9_.arc 109 1 6 A 12-FEB-07 Name: /orcva/PROD/archivelog/2007_02_13/o1_mf_1_6_2x3bbqym_.arc 157 1 7 A 13-FEB-07 Name: /orcva/PROD/archivelog/2007_02_13/o1_mf_1_7_2x3w2cvs_.arc 164 1 8 A 13-FEB-07 Name: /orcva/PROD/archivelog/2007_02_13/o1_mf_1_8_2x3w40vr_.arc 171 1 9 A 13-FEB-07 Name: /orcva/PROD/archivelog/2007_02_13/o1_mf_1_9_2x3w8pf7_.arc 318 1 10 A 13-FEB-07 Name: /orcva/PROD/archivelog/2007_02_13/o1_mf_1_10_2x3zx6d9_.arc 330 1 11 A 13-FEB-07 Name: /orcva/PROD/archivelog/2007_02_13/o1_mf_1_11_2x403wco_.arc 448 1 12 A 13-FEB-07 Name: /orcva/PROD/archivelog/2007_02_13/o1_mf_1_12_2x40wn6x_.arc 455 1 13 A 13-FEB-07 Name: /orcva/PROD/archivelog/2007_02_13/o1_mf_1_13_2x412s3m_.arc 583 1 14 A 13-FEB-07 Name: /orcva/PROD/archivelog/2007_02_13/o1_mf_1_14_2x428p9d_.ar 638 1 15 A 13-FEB-07 Name: /orcva/PROD/archivelog/2007_02_13/o1_mf_1_15_2x42f0gj_.arc Do you really want to delete the above objects (enter YES or NO)?
Example 2-68 Forcing the Deletion of a Backup Set
The following example attempts to delete the backup set copy with tag weekly_bkup
:
RMAN> DELETE NOPROMPT BACKUPSET TAG weekly_bkup;
RMAN displays a warning because the repository shows the backup set as available, but the object is not actually available on the media:
List of Backup Pieces BP Key BS Key Pc# Cp# Status Device Type Piece Name ------- ------- --- --- ----------- ----------- ---------- 809 806 1 1 AVAILABLE SBT_TAPE 0ri9uu08_1_1 RMAN-06207: WARNING: 1 objects could not be deleted for SBT_TAPE channel(s) due RMAN-06208: to mismatched status. Use CROSSCHECK command to fix status RMAN-06210: List of Mismatched objects RMAN-06211: ========================== RMAN-06212: Object Type Filename/Handle RMAN-06213: --------------- --------------------------------------------------- RMAN-06214: Backup Piece 0ri9uu08_1_1
The following command forces RMAN to delete the backup set (sample output included):
RMAN> DELETE FORCE NOPROMPT BACKUPSET TAG weekly_bkup; using channel ORA_SBT_TAPE_1 using channel ORA_DISK_1 List of Backup Pieces BP Key BS Key Pc# Cp# Status Device Type Piece Name ------- ------- --- --- ----------- ----------- ---------- 809 806 1 1 AVAILABLE SBT_TAPE 0ri9uu08_1_1 deleted backup piece backup piece handle=0ri9uu08_1_1 RECID=26 STAMP=614430728 Deleted 1 objects