Oracle 1Z0-083 Online Practice Questions and Exam Preparation

Oracle 1Z0-083 Online Questions & Answers

• Question 71:

  The HR_ROOT application container must support the execution of a query on a table shared by application local PDBs PDB1 and PDB2, and remote PDB PDB3. Which three are true? (Choose three.)

  A. A proxy PDB must exist in the application root in the remote CDB.
  B. A database link must exist in the local CDB root referring to the remote CDB.
  C. PDB3's application root replica must exist in the local CDB.
  D. A database link must exist in the remote CDB referring to the local CDB.
  E. The HR_ROOT replica must exist in the remote CDB.
  F. A proxy PDB must exist in the application root in the local CDB.
  B. A database link must exist in the local CDB root referring to the remote CDB.
  E. The HR_ROOT replica must exist in the remote CDB.
  F. A proxy PDB must exist in the application root in the local CDB.

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  Explanation/Reference:

  Database link must be created in master application root (local CDB) referring to replica application root (remote CDB). Option B Proxy PDB must be created in master application root (local CDB) using this database link. Option F Replica application root must exist in remote CDB (created or upgraded using SYNC in local Proxy PDB). Option E With this, we can make a SELECT that will show data from local and remote PDB applications (Query in local master application root using CONTAINERS clause).

• Question 72:

  RMAN has just been connected to a target database and the recovery catalog database.

  In which two cases would an automatic full resynchronization occur between this target database's control file and the RMAN recovery catalog? (Choose two.)

  A. when control file metadata for archive log backups or image copies has been overwritten in the target database's control file due to being older than CONTROL_FILE_RECORD_KEEP_TIME
  B. when control file metadata for data file backups or image copies has been overwritten in the target database's control file due to being older than CONTROL_FILE_RECORD_KEEP_TIME
  C. when a new tablespace is added to a registered target database
  D. when a backup of the current control file is created
  E. when the target is first registered
  C. when a new tablespace is added to a registered target database
  E. when the target is first registered

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  Explanation/Reference:

  In a full resynchronization, RMAN updates all changed records, including those for the database schema. RMAN performs a full resynchronization after structural changes to database (adding or dropping database files, creating new incarnation, and so on) or after changes to the RMAN persistent configuration. When a database is registered with a recovery catalog for the first time a full catalog synchronization is performed

  https://docs.oracle.com/en/database/oracle/oracle-database/19/bradv/managing-recovery-catalog.html#GUID-6B077FE7-8E10-4603-8FDB-CAE3357E85C9 https://www.oracledistilled.com/oracle-database/backup-and-recovery/registering-a-database-with-a-recovery-catalog/#:~:text=Using%20RMAN%2C%20connect%20to%20both,register)%20and%20the%20recovery%20catalog.andtext=Next% 20issue%20the%20REGISTER%20DATABASE%20command%20to%20register%20the%20database.andtext=When%20a%20database%20is%20registered,is%20performed%20(%20RESYNC%20CATALOG%20).

• Question 73:

  Which three capabilities require the use of the RMAN recovery catalog? (Choose three.)

  A. using the KEEP FOREVER clause with the BACKUP command
  B. using RMAN stored scripts
  C. using the REPORT SCHEMA command to list a database's current data files and tablespaces
  D. creating customized reports about a single database's backups
  E. creating encrypted backups
  F. using the REPORT SCHEMA command to list a database's data files and tablespaces at times in the past
  A. using the KEEP FOREVER clause with the BACKUP command
  B. using RMAN stored scripts
  F. using the REPORT SCHEMA command to list a database's data files and tablespaces at times in the past

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  Explanation/Reference:

  A is correct:

  https://docs.oracle.com/en/database/oracle/oracle-database/19/rcmrf/keepOption.html

  "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."

  B is correct:

  https://docs.oracle.com/database/121/RCMRF/rcmsynta013.htm

  "Execute CREATE SCRIPT only at the RMAN prompt. RMAN must be connected to a target database and a recovery catalog."

  F is correct:

  https://docs.oracle.com/en/database/oracle/oracle-database/19/rcmrf/REPORT.html

  "atClause

  This subclause specifies a point in time as a time, SCN, or log sequence number. You must be connected to a recovery catalog when issuing a REPORT SCHEMA command with an AT clause."

  Reference: https://docs.oracle.com/en/database/oracle/oracle-database/19/bradv/managing-recovery-catalog.html#GUID-2491887B-D9AC-48BE-914D-CB0341A77057

• Question 74:

  You want to duplicate one of your databases when connected to the target database and to the recovery catalog.

  Which three are true about this type of database duplication? (Choose three)

  A. The target database must be open
  B. The duplication process can use existing backup sets or image copies
  C. The duplication process can use existing backup sets or image copies.
  D. The target database must be in mount state.
  E. The duplication -process pushes backup sets to the auxiliary instance.
  F. The duplication process pushes image copies to the auxiliary instance.
  A. The target database must be open
  C. The duplication process can use existing backup sets or image copies.
  F. The duplication process pushes image copies to the auxiliary instance.

• Question 75:

  Examine this configuration:

  1.

  CDB1 is a container database.

  2.

  There are several pluggable databases (PDBs) in CDB1.

  5.

  Each PDB has several tables with referential integrity constraints.

  6.

  FLASHBACK DATABASE is ON.

  7.

  UNDO RETENTION GUARANTEE is enabled.

  Multiple undesired multitable changes were made in all the PDBs.

  Which method can be used to undo the changes using a single command?

  A. restore and recover database
  B. flashback transaction
  C. flashback database
  D. flashback table and transaction
  E. flashback table
  C. flashback database

• Question 76:

  Identify three benefits of Unified Auditing.

  A. Decreased use of storage to store audit trail rows in the database.
  B. It improves overall auditing performance.
  C. It guarantees zero-loss auditing.
  D. The audit trail cannot be easily modified because it is read-only.
  E. It automatically audits Recovery Manager (RMAN) events.
  B. It improves overall auditing performance.
  D. The audit trail cannot be easily modified because it is read-only.
  E. It automatically audits Recovery Manager (RMAN) events.

• Question 77:

  (Choose two) You configured the Fast Recovery Area (FRA) for your database. The database instance is in ARCHIVELOG mode. The default location for the archived redo log files is the FRA. Which two files are removed automatically if space is required in the FRA as per the retention policy?

  A. user-managed backups of data files and control files
  B. flashback logs
  C. RMAN backups that are obsolete
  D. archived redo log files that have multiple copies in a different archive location
  B. flashback logs
  C. RMAN backups that are obsolete

• Question 78:

  In which two situations can you use Database Upgrade Assistant? (Choose two.)

  A. when the operating system (OS) needs to be changed as part of the upgrade
  B. when a character set conversion is required during the upgrade
  C. when multiple pluggable databases in a container database have to be upgraded in a specific sequence
  D. when the target and source database are on the same platform
  E. when the hardware platform needs to be changed as part of the upgrade
  C. when multiple pluggable databases in a container database have to be upgraded in a specific sequence
  D. when the target and source database are on the same platform

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  Explanation/Reference:

  Reference: https://docs.oracle.com/en/database/oracle/oracle-database/12.2/upgrd/upgrading-oracle-database-upgrade-assistant-dbua.html#GUID-F929338D-48EE-434F-A5F9-A9E7CD61B17F

• Question 79:

  Which three are true about Automatic Workload Repository (AWR) snapshots? (Choose three.)

  A. They are generated if STATISTICS_LEVEL is set to TYPICAL.
  B. They are generated if STATISTICS_LEVEL is set to ALL.
  C. They are always created automatically.
  D. They are always created manually.
  E. They can be retained forever.
  F. They are generated if STATISTICS_LEVEL is set to BASIC.
  A. They are generated if STATISTICS_LEVEL is set to TYPICAL.
  B. They are generated if STATISTICS_LEVEL is set to ALL.
  E. They can be retained forever.

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  Explanation/Reference:

  A - TRUE. Only STATISTICS_LEVEL=BASIC stops them being generated B - TRUE. Only STATISTICS_LEVEL=BASIC stops them being generated C - FALSE. You can create them manually. D - FALSE. The DB will, by default, create them automatically every hour E - TRUE. You can setup AWR Warehouse, allowing these reports to be kept, and queried, forever. F - FALSE. STATISTICS_LEVEL=BASIC stops them being generated

  So, ABE is correct.

  Ref: https://docs.oracle.com/en/database/oracle/oracle-database/19/refrn/STATISTICS_LEVEL.html

• Question 80:

  While backing up to the Oracle Fast Recovery Area (FRA), you determined the backup is taking too long and suspect a performance bottleneck. Which three are true about diagnosing and tuning these problems? (Choose three.)

  A. If an RMAN BACKUP VALIDATE command takes roughly the same time as an actual backup, then both read and write I/O are likely bottlenecks.
  B. Setting DBWR_IO_SLAVES to a non zero value can improve backup performance when using synchronous I/O.
  C. If an RMAN BACKUP VALIDATE command takes noticeably less than an actual backup, then write I/O is a likely bottleneck.
  D. If an RMAN BACKUP VALIDATE command takes roughly the same time as an actual backup, then read I/O is a likely bottleneck.
  E. Data files with a high value in V$BACKUP_SYNC_IO.DISCRETE_BYTES_PER_SECOND are a potential performance bottleneck when synchronous I/O is used.
  F. Setting DBWR_IO_SLAVES to a non zero value can improve backup performance when using asynchronous I/O/
  G. Data files with a high value in V$BACKUP_ASYNC_IO.SHORT_WAITS are a potential performance bottleneck when asynchronous I/O is used.
  B. Setting DBWR_IO_SLAVES to a non zero value can improve backup performance when using synchronous I/O.
  C. If an RMAN BACKUP VALIDATE command takes noticeably less than an actual backup, then write I/O is a likely bottleneck.
  D. If an RMAN BACKUP VALIDATE command takes roughly the same time as an actual backup, then read I/O is a likely bottleneck.

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  Explanation/Reference:

  One reliable way to determine whether the output device or input disk I/O is the bottleneck in a given backup job is to compare the time required to run backup tasks with the time required to run BACKUP VALIDATE of the same tasks.

  BACKUP VALIDATE of a backup performs the same disk reads as a real backup but performs no I/O to an output device.

  D -> If the time for the BACKUP VALIDATE to tape is about the same as the time for a real backup to tape, then reading from disk is the likely bottleneck.

  C -> If the time for the BACKUP VALIDATE to tape is significantly less than the time for a real backup to tape, then writing to the output device is the likely bottleneck.

  B -> Some operating systems support native asynchronous I/O. If and only if your disk does not support asynchronous I/O, then set DBWR_IO_SLAVES. Any nonzero value for DBWR_IO_SLAVES causes a fixed number of disk I/O slaves to

  be used for backup and restore, which simulates asynchronous I/O.

  G -> incorrect - The simplest way to identify the bottleneck is to find the data file that has the largest ratio for LONG_WAITS divided by IO_COUNT

  Reference: https://web.stanford.edu/dept/itss/docs/oracle/10gR2/backup.102/b14191/rcmtunin003.htm