OCP-1Z0-053-V12.02-592题

592.Which backup option defines a user-defined name for a backup?

A. FORMAT

B. NAME

C. TAG

D. FORMAT U%

Answer: C

答案解析:

参考:http://docs.oracle.com/cd/E11882_01/backup.112/e10643/rcmsynta007.htm#RCMRF90026



TAG tag_name Specifies a user-specified tag name for a backup set, proxy copy, data file copy, or control file copy. The tag is applied to the output files generated by the BACKUP command.

The tag name is not case-sensitive. The name must be 30 characters or less. The characters are limited to the characters that are valid in file names on the target file system. For example, ASM does not support the use of the hyphen (-) character in the file names it uses internally, so weekly-incremental is not a valid tag name for backups in ASM disk groups. Environment variables are not valid in the TAG parameter.

Typically, a tag name is a meaningful name such as MON_PM_BKUP or WEEKLY_FULL_BKUP. Tags are reusable, so that backup set 100 can have the tag MON_PM_BKUP one week while backup set 105 has the same tag the next week.

If you do not specify a tag name, then by default RMAN creates a tag for backups (except for control file autobackups). The default tag uses the format TAGYYYYMMDDTHHMMSS, where YYYY is the year, MM is the month, DDis the day, HH is the hour (in 24-hour format), MM is the minutes, and SS is the seconds. For example, a backup of data file 1 might receive the tag TAG20070208T133437. The date and time refer to when RMAN started the backup. If multiple backup sets are created by one BACKUP AS BACKUPSET command, then each backup piece is assigned the same default tag.

You can also specify the tag at the backupSpec level. If you specify the tag at:

  • The command level, then all backup sets created by the command have the tag.

  • The backupSpec level, then backup sets created with different backup specifications can have different tags.

  • Both levels, then the tag in the backupSpec takes precedence.

Note: A tag is an attribute of each backup piece in a given copy of a backup set (for AS BACKUPSET) or each image copy (for AS COPY). For example, if you run BACKUP AS BACKUPSET COPIES 1 DATABASE TAG TUE_PM, then only one copy of the backup set exists and each backup piece has tag TUE_PM. Assume that this backup set has primary key 1234. If you then run BACKUP BACKUPSET 1234 TAG WED_PM, then the first copy of the backup set has tag TUE_PM and the second copy of the backup set has tag WED_PM.

原文地址:https://www.cnblogs.com/hzcya1995/p/13316406.html