Oracle Oracle Certifications 1Z0-062 Questions & Answers

• Question 381:

  Examine the following impdp command to import a database over the network from a pre-12c Oracle database (source): Which three are prerequisites for successful execution of the command? (Choose three.)

  

  A. The import operation must be performed on the target database by a user with the DATAPUMP_IMP_FULL_DATABASE role, and the database link must connect to a user with the DATAPUMP_EXP_FULL_DATABASE role on the source database.

  B. All user-defined tablespaces must be in read-only mode on the source database.

  C. The export dump file must be created before starting the import on the target database.

  D. The source and target database must be running on the same operating system (OS) with the same endianness.

  E. The impdp operation must be performed by the same user that performed the expdp operation.

  Correct Answer: ABD

  In this case we have run the impdp without performing any conversion if endian format is different then we have to first perform conversion.

• Question 382:

  Which two are true concerning a multitenant container database with three pluggable database? (Choose two.)

  A. All administration tasks must be done to a specific pluggable database.

  B. The pluggable databases increase patching time.

  C. The pluggable databases reduce administration effort.

  D. The pluggable databases are patched together.

  E. Pluggable databases are only used for database consolidation.

  Correct Answer: CD

• Question 383:

  Examine the current value for the following parameters in your database instance:

  SGA_MAX_SIZE = 1024M SGA_TARGET = 700M DB_8K_CACHE_SIZE = 124M LOG_BUFFER = 200M

  You issue the following command to increase the value of DB_8K_CACHE_SIZE:

  SQL> ALTER SYSTEM SET DB_8K_CACHE_SIZE=140M;

  Which statement is true?

  A. It fails because the DB_8K_CACHE_SIZE parameter cannot be changed dynamically.

  B. It succeeds only if memory is available from the autotuned components if SGA.

  C. It fails because an increase in DB_8K_CACHE_SIZE cannot be accommodated within SGA_TARGET.

  D. It fails because an increase in DB_8K_CACHE_SIZE cannot be accommodated within SGA_MAX_SIZE.

  Correct Answer: D

  *

  The SGA_TARGET parameter can be dynamically increased up to the value specified for the

  SGA_MAX_SIZE parameter, and it can also be reduced.

  *

  Example:

  For example, suppose you have an environment with the following configuration:

  SGA_MAX_SIZE = 1024M SGA_TARGET = 512M DB_8K_CACHE_SIZE = 128M In this example, the value of SGA_TARGET can be resized up to 1024M and can also be reduced until one or more of the automatically sized components reaches its minimum size. The exact value depends on environmental factors such as the number of CPUs on the system. However, the value of DB_8K_CACHE_SIZE remains fixed at all times at 128M

  *

  DB_8K_CACHE_SIZE Size of cache for 8K buffers

  *

  For example, consider this configuration:

  SGA_TARGET = 512M DB_8K_CACHE_SIZE = 128M In this example, increasing DB_8K_CACHE_SIZE by 16 M to 144M means that the 16M is taken away from the automatically sized components. Likewise, reducing DB_8K_CACHE_SIZE by 16M to 112M means that the 16M is given to the automatically sized components.

• Question 384:

  Your database supports a DSS workload that involves the execution of complex queries: Currently, the library cache contains the ideal workload for analysis. You want to analyze some of the queries for an application that are cached in the library cache.

  What must you do to receive recommendations about the efficient use of indexes and materialized views to improve query performance?

  A. Create a SQL Tuning Set (STS) that contains the queries cached in the library cache and run the SQL Tuning Advisor (STA) on the workload captured in the STS.

  B. Run the Automatic Workload Repository Monitor (ADDM).

  C. Create an STS that contains the queries cached in the library cache and run the SQL Performance Analyzer (SPA) on the workload captured in the STS.

  D. Create an STS that contains the queries cached in the library cache and run the SQL Access Advisor on the workload captured in the STS.

  Correct Answer: D

  *

  SQL Access Advisor is primarily responsible for making schema modification recommendations, such as adding or dropping indexes and materialized views. SQL Tuning Advisor makes other types of

  recommendations, such as creating SQL profiles and restructuring SQL statements.

  *

  The query optimizer can also help you tune SQL statements. By using SQL Tuning Advisor and SQL Access Advisor, you can invoke the query optimizer in advisory mode to examine a SQL statement or set of statements and determine how to improve their efficiency. SQL Tuning Advisor and SQL Access Advisor can make various recommendations, such as creating SQL profiles, restructuring SQL statements, creating additional indexes or materialized views, and refreshing optimizer statistics.

  Note:

  *

  Decision support system (DSS) workload

  *

  The library cache is a shared pool memory structure that stores executable SQL and PL/SQL code. This cache contains the shared SQL and PL/SQL areas and control structures such as locks and library cache handles.

• Question 385:

  The following parameter are set for your Oracle 12c database instance:

  OPTIMIZER_CAPTURE_SQL_PLAN_BASELINES=FALSE OPTIMIZER_USE_SQL_PLAN_BASELINES=TRUE

  You want to manage the SQL plan evolution task manually. Examine the following steps:

  1.

  Set the evolve task parameters.

  2.

  Create the evolve task by using the DBMS_SPM.CREATE_EVOLVE_TASK function.

  3.

  Implement the recommendations in the task by using the DBMS_SPM.IMPLEMENT_EVOLVE_TASK function.

  4.

  Execute the evolve task by using the DBMS_SPM.EXECUTE_EVOLVE_TASK function.

  5.

  Report the task outcome by using the DBMS_SPM.REPORT_EVOLVE_TASK function.

  Identify the correct sequence of steps:

  A. 2, 4, 5

  B. 2, 1, 4, 3, 5

  C. 1, 2, 3, 4, 5

  D. 1, 2, 4, 5

  Correct Answer: B

  * Evolving SQL Plan Baselines *

  

  2. Create the evolve task by using the DBMS_SPM.CREATE_EVOLVE_TASK function.

  This function creates an advisor task to prepare the plan evolution of one or more plans for a specified

  SQL statement. The input parameters can be a SQL handle, plan name or a list of plan names, time limit,

  task name, and description.

  1. Set the evolve task parameters.

  SET_EVOLVE_TASK_PARAMETER

  This function updates the value of an evolve task parameter. In this release, the only valid parameter is

  TIME_LIMIT.

  4. Execute the evolve task by using the DBMS_SPM.EXECUTE_EVOLVE_TASK function.

  This function executes an evolution task. The input parameters can be the task name, execution name,

  and execution description. If not specified, the advisor generates the name, which is returned by the

  function.

  3: IMPLEMENT_EVOLVE_TASK

  This function implements all recommendations for an evolve task. Essentially, this function is equivalent to

  using ACCEPT_SQL_PLAN_BASELINE for all recommended plans. Input parameters include task name,

  plan name, owner name, and execution name.

  5. Report the task outcome by using the DBMS_SPM_EVOLVE_TASK function.

  This function displays the results of an evolve task as a CLOB. Input parameters include the task name

  and section of the report to include.

• Question 386:

  In a recent Automatic Workload Repository (AWR) report for your database, you notice a high number of buffer busy waits. The database consists of locally managed tablespaces with free list managed segments.

  On further investigation, you find that buffer busy waits is caused by contention on data blocks.

  Which option would you consider first to decrease the wait event immediately?

  A. Decreasing PCTUSED

  B. Decreasing PCTFREE

  C. Increasing the number of DBWN process

  D. Using Automatic Segment Space Management (ASSM)

  E. Increasing db_buffer_cache based on the V$DB_CACHE_ADVICE recommendation

  Correct Answer: D

  *

  Automatic segment space management (ASSM) is a simpler and more efficient way of managing space within a segment. It completely eliminates any need to specify and tune the pctused,freelists, and freelist groups storage parameters for schema objects created in the tablespace. If any of these attributes are specified, they are ignored.

  *

  Oracle introduced Automatic Segment Storage Management (ASSM) as a replacement for traditional freelists management which used one-way linked-lists to manage free blocks with tables and indexes. ASSM is commonly called "bitmap freelists" because that is how Oracle implement the internal data structures for free block management.

  Note:

  *

  Buffer busy waits are most commonly associated with segment header contention onside the data buffer pool (db_cache_size, etc.).

  *

  The most common remedies for high buffer busy waits include database writer (DBWR) contention tuning, adding freelists (or ASSM), and adding missing indexes.

• Question 387:

  Which action takes place when a file checkpoint occurs?

  A. The checkpoint position is advanced in the checkpoint queue.

  B. All buffers for a checkpointed file that were modified before a specific SCN are written to disk by DBWn and the SCN is stored in the control file.

  C. The Database Writer process (DBWn) writes all dirty buffers in the buffer cache to data files.

  D. The Log Writer process (LGWR) writes all redo entries in the log buffer to online redo log files.

  Correct Answer: B

• Question 388:

  Examine the structure of the sales table, which is stored in a locally managed tablespace with Automatic Segment Space Management (ASSM) enabled.

  

  You want to perform online segment shrink to reclaim fragmented free space below the high water mark. What should you ensure before the start of the operation?

  A. Row movement is enabled.

  B. Referential integrity constraints for the table are disabled.

  C. No queries are running on this table.

  D. Extra disk space equivalent to the size of the segment is available in the tablespace.

  E. No pending transaction exists on the table.

  Correct Answer: A

• Question 389:

  Which task would you recommend before using the Database Upgrade Assistant (DBUA) to upgrade a single-instance Oracle 11g R2 database to Oracle Database 12c?

  A. shutting down the database instance that is being upgraded

  B. executing the catctl.pl script to run the upgrade processes in parallel

  C. running the Pre-Upgrade Information Tool

  D. copying the listener.ora file to the new ORACLE_HOME

  Correct Answer: C

  References: http://docs.oracle.com/cd/E11882_01/server.112/e23633/upgrade.htm#UPGRD12395

• Question 390:

  Your database is open and the listener LISTENER is up. You issue the command:

  LSNRCTL> RELOAD

  What is the effect of reload on sessions that were originally established by listener?

  A. Only sessions based on static listener registrations are disconnected.

  B. Existing connections are not disconnected; however, they cannot perform any operations until the listener completes the re-registration of the database instance and service handlers.

  C. The sessions are not affected and continue to function normally.

  D. All the sessions are terminated and active transactions are rolled back.

  Correct Answer: C