1Z0-052 · Question #98
You are working on a database that must be functioning 24 hours a day, 7 days a week. The database is configured in ARCHIVELOG mode. Which two options do you have for performing user-managed…
The correct answer is B. You can perform a complete database backup without shutting down the database instance. D. You can back up only those data files whose headers are frozen by using ALTER TABLESPACE. In ARCHIVELOG mode, user-managed online backups are possible by using ALTER TABLESPACE ... BEGIN BACKUP to freeze data file headers, allowing backup of open data files without shutting down.
Question
You are working on a database that must be functioning 24 hours a day, 7 days a week. The database is configured in ARCHIVELOG mode. Which two options do you have for performing user-managed backups? (Choose two.)
Options
- AYou can perform consistent backups only.
- BYou can perform a complete database backup without shutting down the database instance.
- CYou can back up data files only when all data files have the same SCN recorded in the control file.
- DYou can back up only those data files whose headers are frozen by using ALTER TABLESPACE
How the community answered
(27 responses)- A7% (2)
- B81% (22)
- C11% (3)
Why each option
In ARCHIVELOG mode, user-managed online backups are possible by using ALTER TABLESPACE ... BEGIN BACKUP to freeze data file headers, allowing backup of open data files without shutting down.
Consistent backups require shutting down the database cleanly so all data files share the same SCN, which directly contradicts the 24x7 availability requirement and is unnecessary in ARCHIVELOG mode.
ARCHIVELOG mode enables inconsistent (open) backups because redo logs archive all changes, allowing Oracle to recover a data file taken at any point back to a consistent state without shutting down the instance.
Requiring all data files to share the same SCN describes a consistent (cold) backup condition, not an online ARCHIVELOG backup, and cannot be satisfied on a running database with active transactions.
Issuing ALTER TABLESPACE <name> BEGIN BACKUP freezes the data file headers for that tablespace, so the OS can copy the files while the database remains open; this is the standard user-managed online backup method.
Concept tested: User-managed online backups in ARCHIVELOG mode
Source: https://docs.oracle.com/en/database/oracle/oracle-database/19/bradv/user-managed-database-backups.html
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