OCP-1Z0-053-V13.02-133题

133.You performed the RMAN database backup with the KEEP option. Which two statements are true regarding this backup? (Choose two.)

A. The backup contains data files, the server parameter file, and the control file even if the control file autobackup is disabled.

B. The KEEP option overrides the configured retention policy.

C. The backup contains only data files and archived redo log files.

D. The KEEP option is an attribute of an individual backup piece.

Answer: AB

答案解析：

参考：http://docs.oracle.com/cd/E11882_01/server.112/e10803/config_backuprec.htm#HABPT5159

Usage Notes

RMAN does not consider backup pieces with the KEEP option when computing the backup retention policy. If available, RMAN uses these backups for disaster recovery restore operations, but their purpose is to produce a snapshot of the database that can be restored on another system for testing or historical usage.

When creating archival backups with KEEP, RMAN only considers KEEP backups with the same tag. Thus, when using keepOption with notBackedUpSpec, RMAN only skips a backup if it finds the specified maximum number of KEEP backups with the same tag. Other backups are not counted.

Semantics

Syntax Element	Description
KEEP	Specifies the backup as an archival backup, which is a self-contained backup that is exempt from the configured retention policy. An archival backup is self-contained because is contains all files necessary to restore the backup and recover it to a consistent state. If the database is open during the backup, then RMAN automatically generates and backs up the archived redo log files needed to make the database backup consistent (see Example 2-26). RMAN does not consider backup pieces with the KEEP option when computing the retention policy. If available, RMAN uses these backups for disaster recovery restore operations, but their purpose is to produce a snapshot of the database that can be restored on another system for testing or historical usage. Note: You cannot use KEEP to override the retention policy for files stored in the fast recovery area. If you specify KEEP when backing up to the recovery area, then RMAN issues an error. When KEEP is specified, RMAN creates multiple backup sets. RMAN backs up data files, archived redo log files, the control file, and the server parameter file with the options specified in the first backupOperand. Since a backup of the control file is already created, an autobackup of the control file is not created. RMAN uses theFORMAT, POOL, and TAG parameters for all the backups. For this reason, the FORMAT string must allow for the creation of multiple backup pieces. Specifying %U is the easiest way to meet this requirement. See Also: CONFIGURE and Oracle Database Backup and Recovery User's Guide to learn more about autobackup of the control file. When KEEP is specified with INCREMENTAL LEVEL, the parent backup must be a KEEP backup and have the sameTAG string. Unless both these criteria are met, the backup cannot be created. Backups that meet these criteria do not interfere with other nightly or archival backup tasks. Note: A recovery catalog is only required for KEEP FOREVER. No other KEEP options require a catalog.
FOREVER	Specifies that the backup or copy never becomes obsolete (see Example 2-27). A recovery catalog is required when FOREVER is specified because the backup records eventually age out of the control file.
UNTIL TIME    'date_string'	Specifies the time until which the backup or copy must be kept. After this time the backup is obsolete, regardless of the backup retention policy settings. You can either specify a specific time by using the current NLS_DATE_FORMAT, or a SQL date expression such as'SYSDATE+365'. If you specify a KEEP TIME such as 01-JAN-07, then the backup becomes obsolete one second after midnight on this date. If you specify a KEEP time such as 9:00 p.m, then the backup becomes obsolete at 9:01 p.m.
RESTORE POINT    restore_point_name	Creates a normal restore point matching the SCN to which RMAN must recover the backup to a consistent state (see Example 2-26). The restore point name must not exist. The SCN is captured just after the data file backups complete. The restore point is a label for the SCN to which this archival backup can be restored and recovered, enabling the database to be opened. In contrast, the UNTIL TIME clause specifies the date until which the backup must be kept. Note: The RESTORE POINT parameter is not valid with the CHANGE command.
NOKEEP	Specifies that any KEEP attributes no longer apply to the backup. Thus, the backup is a normal backup that is subject to the configured backup retention policy. This is the default behavior if no KEEP option is specified.

Examples

Example 4-23 Creating a Consistent Database Backup for Archival

This example makes a database backup with tag Q107 and specifies that it should never be considered obsolete (partial sample output included). The archived redo log files necessary to make the data files consistent are included in the backup set.

RMAN> BACKUP TAG Q107 DATABASE KEEP FOREVER;

 

Starting backup at 24-JAN-07

 

current log archived

allocated channel: ORA_SBT_TAPE_1

channel ORA_SBT_TAPE_1: SID=105 device type=SBT_TAPE

channel ORA_SBT_TAPE_1: Oracle Secure Backup

backup will never be obsolete

archived logs required to recover from this backup will be backed up

channel ORA_SBT_TAPE_1: starting full datafile backup set

channel ORA_SBT_TAPE_1: specifying datafile(s) in backup set

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Example 4-24 Removing the KEEP Attributes for a Backup

This example backs up all archived redo log files. The KEEP clause specifies that one second after midnight on January 1, 2008 the backup is considered obsolete.

RMAN> BACKUP KEEP UNTIL TIME '01-JAN-08' ARCHIVELOG ALL;

The following command removes the KEEP attributes of all archived redo log backups (sample output included):

RMAN> CHANGE BACKUP OF ARCHIVELOG ALL NOKEEP;

 

using channel ORA_SBT_TAPE_1

allocated channel: ORA_DISK_1

channel ORA_DISK_1: SID=77 device type=DISK

keep attributes for the backup are deleted

backup set key=330 RECID=19 STAMP=612722760

keep attributes for the backup are deleted

backup set key=397 RECID=22 STAMP=612722884