Free 1z0-083 sample questions

Correct answers: relocating a remote pluggable database in silent mode; cloning a remote container database in silent mode; cloning a remote pluggable database in silent mode

Oracle Database 19c added the DBCA relocatePDB command. It relocates a PDB from another CDB in silent mode.

Oracle Database 19c added the DBCA createDuplicateDB command. It creates a duplicate (clone) of an existing database in silent mode.

Oracle Database 19c added the createFromRemotePDB option to the DBCA createPluggableDatabase command. It clones a remote PDB in silent mode.

Correct answer: Execute FLASHBACK PLUGGABLE DATABASE PDB1 TO RESTORE POINT R1 by using RMAN while connected to CDB$ROOT.

PDB1 uses shared undo. R1 is not a clean restore point, so SQL*Plus cannot do the flashback. RMAN, connected to the root, does it with an auxiliary instance that restores undo from the backup.

Correct answer: V$SESSION_EVENT

V$SESSION_EVENT has a row for each wait event that a session has waited on, with its total waits and time waited. V$SESSION_WAIT shows only the current or last wait.

Correct answers: If an RMAN BACKUP VALIDATE command takes noticeably less time than an actual backup, then write I/O is a likely bottleneck.; If an RMAN BACKUP VALIDATE command takes roughly the same time as an actual backup, then read I/O is a likely bottleneck.; Setting DBWR_IO_SLAVES to a nonzero value can improve backup performance when using synchronous I/O.

BACKUP VALIDATE reads the files like a real backup but writes nothing. If it is much faster than the real backup, writing to the output device is the slow part.

BACKUP VALIDATE does the same reads as a real backup but no writes. If both take about the same time, reading from disk is the slow part.

With synchronous disk I/O, a nonzero DBWR_IO_SLAVES makes RMAN use disk I/O slaves. They simulate asynchronous I/O, which can speed up the backup.

Correct answers: Privilege Analysis is included in Oracle Enterprise Edition and no longer requires Database Vault.; Schema Only accounts can be granted administrator privileges.; Unified Auditing can be configured to audit only events that are issued directly by an audited user.

In 19c, privilege analysis is part of Oracle Database Enterprise Edition. You no longer need a Database Vault license to find used and unused privileges.

From 19c you can grant administrative privileges such as SYSOPER or SYSBACKUP to schema-only (passwordless) accounts.

From 19c, unified auditing can audit only top-level statements, which a user issues directly. Indirect statements, for example inside PL/SQL, are then skipped.

Correct answers: SBT tape compression can be used even if no RMAN compression is configured.; The SBT device should be configured to use PARALLELISM 2 to allow both tape drives to be used simultaneously.

The media manager or the tape device does tape compression. It does not depend on RMAN. Use either tape compression or RMAN compression, not both.

Each tape drive needs its own channel. CONFIGURE DEVICE TYPE sbt PARALLELISM 2 gives two SBT channels, so RMAN writes to both drives at the same time.

Correct answers: to switch to a patched Oracle Database home; to switch back to the previous Oracle home as part of a rollback operation

With home paths instead of working copies, this is the local-mode patching command. It moves the database from its current home to a home that already has the patches.

If a problem appears after a move, you roll back by running the same move again with the source and destination homes swapped.

Correct answers: The NOREDO clause must be used if the backups of the database being duplicated were taken when the database was in NOARCHIVELOG mode.; RMAN disk-based backups of the database to be duplicated can be used by the auxiliary instance.; The NOREDO clause can be used if the backups of the database being duplicated were taken when the database was in ARCHIVELOG mode.; RMAN SBT-based backups of the database to be duplicated can be used by the auxiliary instance.

Without a target connection, RMAN cannot tell that the source was in NOARCHIVELOG mode. You must add NOREDO so that RMAN does not try to apply archived redo.

Disk backups can be used when the destination host can read them, either at the same path as on the source or through the BACKUP LOCATION clause.

NOREDO can also be used with backups taken in ARCHIVELOG mode when the backup is consistent and you do not want any archived redo applied.

Backup-based duplication can use backups on tape. The auxiliary channels read them through the media manager, which the destination host must be able to reach.

Correct answers: A snapshot copy PDB can be created from a stand-alone clone PDB.; A snapshot copy PDB depends on a storage snapshot which can only be stored on specific file systems.

A clone made from a PDB snapshot with USING SNAPSHOT is a full standalone PDB. You can then create a snapshot copy PDB from that clone.

A snapshot copy PDB is built on a storage-managed snapshot. Storage-managed snapshots are supported only on specific file systems.

Correct answers: Flashback logs are automatically purged when DB_FLASHBACK_RETENTION_TARGET is set lower than the time they have already been retained; Flashback logs are monitored and proactively deleted when beyond the retention period defined in DB_FLASHBACK_RETENTION_TARGET before there is space pressure.

In 19c, when you lower DB_FLASHBACK_RETENTION_TARGET, flashback logs older than the new target are deleted at once.

In 19c, the database monitors flashback logs. It deletes logs beyond the retention target on its own, without waiting for space pressure in the fast recovery area.