Oracle Oracle Certifications 1Z0-083 Questions & Answers

• Question 251:

  Examine this output:

  

  Which two are true? (Choose two.)

  A. Any PDB not specified in the plan will be unable to execute statements in parallel.

  B. PDB3 can use all available parallel execution processes at times.

  C. PDB1 is always limited to 40% of the available system resources regardless of demand.

  D. Any PDB not specified in the plan will be able to use a maximum of 16.5% of the available system resources.

  E. PDB3 is guaranteed to receive at least 20% of the available system resources if there is enough demand.

  F. PDB2 is guaranteed at least 25% of the available parallel execution processes if there is enough demand.

  Correct Answer: BF

  A- Incorrect : If PARALLEL_SERVER_LIMIT is not specified, then it defaults to 100%

  REF: https://docs.oracle.com/database/121/ADMIN/dbrm.htm#ADMIN14007

  https://docs.oracle.com/en/database/oracle/oracle-database/19/multi/using-oracle-resource-manager-for-pdbs-with-sql-plus.html#GUID-3E84009E-5CD6-46B8-84D3-BE775D58D9AA

  When you do not explicitly define directives for a PDB, the PDB uses the default directive for PDBs.

  B - Correct : If PARALLEL_SERVER_LIMIT is not specified, then it defaults to 100%

  C - Incorrect: PDB1 is NOT always limited to 40% of the available system resources regardless of demand.

  D - Incorrect : When you do not explicitly define directives for a PDB, the PDB uses the default directive for PDBs., default is 100%

  E: Incorrect : available system resources = utilization_limit and parallel_server_limit

  F: Correct : parallel_server_limit =25

• Question 252:

  Which two are true about gathering optimizer statistics? (Choose two.)

  A. Executing DBMS_STATS.GATHER_DATABASE_STATS while connected to CDB$ROOT gathers object statistics in all open PDBs except PDB$SEED.

  B. Executing DBMS_STATS.GATHER_DATABASE_STATS while connected to a PDB opened in read/write mode gathers object statistics for that PDB.

  C. Executing DBMS_STATS.GATHER_DATABASE_STATS while connected to CDB$ROOT gathers object statistics only in CDB$ROOT.

  D. System statistics can be gathered only while connected to CDB$ROOT.

  E. Executing DBMS_STATS.GATHER_DATABASE_STATS while connected to CDB$ROOT gathers object statistics in all open pluggable databases (PDBs)

  Correct Answer: BC

  BC test:

  SQL> select count(*) from sys.dba_tab_statistics where last_analyzed is not null;

  COUNT(*)

  3610

  SQL> EXEC DBMS_STATS.GATHER_DATABASE_STATS;

  PL/SQL procedure successfully completed.

  SQL> select count(*) from sys.dba_tab_statistics where last_analyzed is not null;

  COUNT(*)

  3649

  SQL> alter session set container=ORCLPDB1;

  Session altered.

  SQL> select count(*) from sys.dba_tab_statistics where last_analyzed is not null; COUNT(*)

  SQL> EXEC DBMS_STATS.GATHER_DATABASE_STATS;

  PL/SQL procedure successfully completed.

  SQL> select count(*) from sys.dba_tab_statistics where last_analyzed is not null;

  COUNT(*)

• Question 253:

  Which three are true about transporting databases across platforms using Recovery Manager (RMAN) image copies? (Choose three.)

  A. By default, the transported database will use Oracle Managed Files (OMF)

  B. Data files can be converted on the destination system.

  C. Data files can be converted on the source system.

  D. A new DBID is automatically created for the transported database.

  E. Databases can be transported between systems with different endian formats.

  F. The password file is automatically converted by RMAN.

  Correct Answer: BCE

  A is wrong. There is no default, file can either be OMF or user managed.

  B is correct. Use the RMAN CONVERT DATABASE ON DESTINATION PLATFORM clause.

  C is correct. Use the RMAN CONVERT DATABASE ENW DATABASE clause.

  D is wrong. Use the DBNEWID Utility (the only way to change a DB's DBID) on the new destination to change the DBID.

  E is correct. We use the RMAN CONVERT clause.

  F is wrong. The password file is "outside" the database and must be manually re-created on the new destination if you do not want to use OS authentication. Also, this file does not need conversion.

• Question 254:

  Examine this command:

  $ rhpctl move database –sourcehome Oracle_home_path –destinationhome Oracle_home_path

  For which two purposes can you use this command? (Choose two.)

  A. to switch an existing Oracle Database home to a newer release of Oracle software on the same server

  B. to switch to a read-only Oracle home

  C. to switch back to the previous Oracle home as part of a rollback operation

  D. to switch the Oracle Database home when using a centralized Rapid Home Provisioning server

  E. to switch to a patched Oracle Database home

  Correct Answer: CE

  You can use rhpctl move gihome command with the same syntax to switch from the current Oracle Grid Infrastructure home to a patched home.

  The rhpctl command enables you to switch from your current Oracle Grid Infrastructure or Oracle Database home to patched Oracle home so that you can provision the new Oracle home as gold image.

  You can also use the rhpctl command to switch back to the old Oracle home, if you want to roll back the operation.

• Question 255:

  Which two are true about changing the LOCAL_UNDO_ENABLED property to false in a CDB? (Choose two.)

  A. After the change, only a common user with the required privilege can create an undo tablespace in CDBandROOT.

  B. Any new PDB and existing PDBs are automatically configured to use the default undo tablespace in CDB$ROOT.

  C. After the change, only one undo tablespace can exist in CDB$ROOT.

  D. After the change, any user with the required privilege can create an undo tablespace in the PDBs.

  E. Undo tablespaces existing in PDBs must be dropped before the change.

  F. After the change, each existing PDB has to be reopened for the new undo mode to take effect.

  Correct Answer: AB

• Question 256:

  Which two are true about SQL Performance Analyzer (SPA)? (Choose two.)

  A. It is integrated with the SQL Access Advisor.

  B. It predicts the impact of system changes on SQL workload response time.

  C. It provides before and after execution statistics for each SQL statement in the analysis task

  D. It offers fine-grained analysis of all the SQL statements in the analysis task as a group.

  E. SQL statements that were originally run concurrently are run concurrently by SPA.

  Correct Answer: BC

  Oracle Real Application Testing ... enables businesses to fully assess the outcome of a system changes in test or production. Oracle Real Application Testing is comprised of the following features: Performance Analyzer (SPA), SPA ...

  C:

  SQL Performance Analyzer executes the SQL statements captured in the SQL Tuning Set and generates execution plans and execution statistics for each statement

  For D , though group (summary) view is shown during analysis, i dont think that what they mean by fine grained

  Reference: https://www.oracle.com/technetwork/database/manageability/spa-ow09-131455.pdf (4)

• Question 257:

  A user complains about poor database performance.

  You want to verify if the user's session has waited for certain types of I/O activity.

  Which view displays all waits waited on by a session at least once?

  A. V$SESSION_EVENT

  B. V$SESSTAT

  C. V$SESSION_WAIT

  D. V$SESSION_WAIT_CLASS

  E. V$SESSION

  Correct Answer: A

  V$SESSION_EVENT, but C. V$SESSION_WAIT can displays the current or last wait for each session. https://docs.oracle.com/en/database/oracle/oracle-database/19/refrn/V-SESSION_EVENT.html#GUID-5723D404-83F7-4C8D-8BF2-031B3FFEAAA8 https://docs.oracle.com/en/database/oracle/oracle-database/19/refrn/V-SESSION_WAIT.html#GUID-4EDAB293-F3FC-40FE-BC75-4FEE6A4D7705

• Question 258:

  Which four are true about duplicating a database using Recovery Manager (RMAN)? (Choose four.)

  A. Duplication can be done by having the auxiliary database instance pull backup sets from the target database instance.

  B. A connection to an auxiliary instance is always required.

  C. A subset of the target database can be duplicated.

  D. A new DBID is always created for the duplicated database.

  E. A connection to the recovery catalog instance is always required.

  F. A backup of the target database is always required.

  G. Duplication can be done by having the target database instance push copies to the auxiliary database instance.

  H. A connection to the target database instance is always required.

  Correct Answer: ABCG

• Question 259:

  A container database called CDB1 is OMF-enabled.

  PDB_FILE_NAME_CONVERT is not configured in CDB1.

  PDB1 was unplugged from CDB1 earlier in the week.

  Examine this command, which will be executed in CDB1:

  CREATE PLUGGABLE DATABASE pdb1

  USING `/u01/app/oracle/oradata/pdb1.xml'

  SOURCE_FILE_NAME_CONVERT =

  (`/u01/app/oracle/oradata/', `/u02/app/oracle/oradata/');

  Which two are true? (Choose two.)

  A. PDB1 data files already exist in the correct location.

  B. DBMS_PDB.CHECK_PLUG_COMPATIBILITY must be run in CDB1 before executing the command.

  C. PDB_FILE_NAME_CONVERT must be set before executing the command.

  D. /u01/app/oracle/oradata/pdb1.xml does not contain the current locations of data files for PDB1.

  E. PDB1 must be dropped from CDB1.

  Correct Answer: DE

• Question 260:

  You must transport the UNIVERSITY tablespace from one database to another.

  The UNIVERSITY tablespace is currently open read/write.

  The source and destination platforms have different endian formats.

  Examine this list of actions:

  1.

  Make the UNIVERSITY tablespace read-only on the source system.

  2.

  Export the UNIVERSITY tablespace metadata using EXPDP.

  3.

  Convert the UNIVERSITY tablespace data fies to the destination platform format using RMAN on the source system.

  4.

  Copy the UNIVERSITY tablespace data files to the destination system.

  5.

  Copy the Data Pump dump set to the destination system.

  6.

  Convert the UNIVERSITY tablespace data files to the destination platform format using RMAN on the destination system.

  7.

  Import the UNIVERSITY tablespace metadata using IMPDP.

  8.

  Make the UNIVERSITY tablespace read/write on the destination system.

  Which is the minimum number of actions required, in the correct order, to transport the UNIVERSITY tablespace?

  A. 1, 2, 4, 5, 7, 8

  B. 1, 2, 4, 6, 7, 8

  C. 1, 2, 3, 4, 5, 7, 8

  D. 1, 2, 3, 4, 5, 6, 7, 8

  E. 2, 4, 5, 6, 7

  Correct Answer: C