1Z0-062 Exams Study Guides
Posted: Aug 08, 2017
Examine the parameters for your database instance:
You execute the following command:
SQL> ALTER TABLESPACE undotbs1 RETENTION NOGUARANTEE;
Which statement is true in this scenario?
A. Undo data is written to flashback logs after 1200 seconds.
B. Inactive undo data is retained for 1200 seconds even if subsequent transactions fail due tolack of space in the undo tablespace.
C. You can perform a Flashback Database operation only within the duration of 1200 seconds.
D. An attempt is made to keep inactive undo for 1200 seconds but transactions may overwrite the undo before that time has elapsed.
A user establishes a connection to a database instance by using an Oracle Net connection. You want to ensure the following:
- The user account must be locked after five unsuccessful login attempts.
- Data read per session must be limited for the user.
- The user cannot have more than three simultaneous sessions.
- The user must have a maximum of 10 minutes session idle time before being logged off automatically.
How would you accomplish this?
A. by granting a secure application role to the user
B. by implementing Database Resource Manager
C. by using Oracle Label Security options
D. by assigning a profile to the user
As a user of the ORCL database, you establish a database link to the remote HQ database such that all users in the ORCL database may access tables only from the SCOTT schema in the HQ database. SCOTT’s password is TIGER. The service mane "HQ" is used to connect to the remote HQ database.
Which command would you execute to create the database link?
A. CREATE DATABASE LINK HQ USING 'HQ';
B. CREATE DATABASE LINK HQ CONNECT TO CURRENT_USER USING ‘HQ’;
C. CREATE PUBLIC DATABASE LINK HQ CONNECT TO scott IDENTIFIED BY tiger USING 'HQ';
D. CREATE DATABASE LINKHQ CONNECT TO scott IDENTIFIED BY tiger USING 'HQ';
What happens if a maintenance window closes before a job that collects optimizer statistics completes?
A. The job is terminated and the gathered statistics are not saved.
B. The job is terminated but the gathered statistics are not published.
C. The job continues to run until all statistics are gathered.
D. The job is terminated and statistics for the remaining objects are collected the next time the maintenance window opens.
The stop_on_window_close attribute controls whether the GATHER_STATS_JOB continues when the maintenance window closes. The default setting for the stop_on_window_close attribute is TRUE, causing Scheduler to terminate GATHER_STATS_JOB when the maintenance window closes. The remaining objects are then processed in the next maintenance window.
You plan to create a database by using the Database Configuration Assistant (DBCA), with the following specifications:
- Applications will connect to the database via a middle tier.
- The number of concurrent user connections will be high.
- The database will have mixed workload, with the execution of complex BI queries scheduled at night.
Which DBCA option must you choose to create the database?
A. a General Purpose database template with defaultmemory allocation
B. a Data Warehouse database template, with the dedicated server mode option and AMM enabled
C. a General Purpose database template, with the shared server mode option and Automatic Memory Management (AMM) enabled
D. a default database configuration
Which two statements are true about the logical storage structure of an Oracle database?
A. An extent contains data blocks that are always physically contiguous on disk.
B. An extent can span multiple segments.
C. Each data block always corresponds to one operating system block.
D. It is possible to have tablespaces of different block sizes.
E. A data block is the smallest unit of I/O in data files.
Which two statements correctly describe the relationship between data files and logical database structures?
A. A segment cannot span data files.
B. A data file can belong to only one tablespace.
C. An extent cannot span data files.
D. The size of an Oracle data blockin a data file should be the same as the size of an OS block.
Which statement is true about the Log Writer process?
A. It writes when it receives a signal from the checkpoint process (CKPT).
B. It writes concurrently to all members of multiplexed redo log groups.
C. It writes after the Database Writer process writes dirty buffers to disk.
D. It writes when a user commits a transaction.
The ORCL database is configured to support shared server mode. You want to ensure that a user connecting remotely to the database instance has a one-to-one ratio between client and server processes.
Which connection method guarantees that this requirement is met?
A. connecting by using an external naming method
B. connecting by using the easy connect method
C. creating a service in the database by using the dbms_service.create_service procedure and using this service for creating a local naming service
D. connecting by using the local naming method with the server = dedicated parameter set in the tnsnames.ora file for the net service
E. connecting by using a directory naming method
Which two tasks can be performed on an external table?
A. partitioningthe table
B. creating an invisible index
C. updating the table by using an update statement
D. creating a public synonym
E. creating a view
Which three statements are true about a job chain?
A. It can contain a nested chain of jobs.
B. It can be used to implement dependency-based scheduling.
C. It cannot invoke the same program or nested chain in multiple steps in the chain.
D. It cannot have more than one dependency.
E. It can be executed using event-based or time-based schedules.
The HR user receives the following error while inserting data into the sales table:
On investigation, you find that the users tablespace uses Automatic Segment Space Management (ASSM). It is the default tablespace for the HR user with an unlimited quota on it.
Which two methods would you use to resolve this error?
A. Altering the data file associated with the USERS tablespace to ex automatically
B. Adding a data file to the USERS tablespace
C. Changing segment space management for the USERS tablespace to manual
D. Creating a new tablespace with autoextend enabled and changing the default tablespace of the HRuser to the new tablespace
E. Enabling resumable space allocation by setting the RESUMABLE_TIMEOUT parameter to a nonzero value
Which three factors influence the optimizer's choice of an execution plan?
A. theoptimizer_mode initialization parameter
B. operating system (OS) statistics
C. cardinality estimates
D. object statistics in the data dictionary
E. fixed baselines
Examine the resources consumed by a database instance whose current Resource Manager plan is displayed.
Which two statements are true?
A. An attempt to start a new session by a user belonging to DSS_QUERIES fails with an error.
B. An attempt to start a new session by a user belonging to OTHER_GROUPS fails with an error.
C. The CPU_WAIT_TIME column indicates the total time that sessions in the consumer group waited for the CPU due to resource management.
D. The CPU_WAIT_TIME column indicates the total time that sessions in the consumer group waited for the CPU due to I/O waits and latch or enqueue contention.
E. A user belonging to the DSS__QUERIES resource consumer group can create a new session but the session will be queued.
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. TheDatabase 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.
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.
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
Your database is open and the listener LISTNENER is up. You issue the command:
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 tofunction normally.
D. All the sessions are terminated and active transactions are rolled back.
Which statement is true regarding the startup of a database instance?
A. The instance does not start up normally andrequires manual media recovery after a shutdown using the abort option.
B. Uncommitted transactions are rolled back during the startup of the database instance after a shutdown using the immediate option.
C. There is no difference in the underlying mechanics of the startup whether the database is shut down by using the immediate option or the abort option.
D. Media recovery is required when the database is shut down by using either the immediate option or the abort option.
E. Instance recovery is not required if the database instance was shut down by using SHUTDOWN IMMEDIATE.
Examine the memory-related parameters set in the SPFILE of an Oracle database:
Which statement is true?
A. Only SGA components are sizedautomatically.
B. Memory is dynamically re-allocated between the SGA and PGA as needed.
C. The size of the PGA cannot grow automatically beyond 500 MB.
D. The value of the MEMORY_TARGET parameter cannot be changed dynamically.
Which two statements are true about extents?
A. Blocks belonging to an extent can be spread across multiple data files.
B. Data blocks in an extent are logically contiguous but can be non-contiguous on disk.
C. The blocks of a newly allocated extent, although free, may have been used before.
D. Data blocks in an extent are automatically reclaimed for use by other objects in a tablespace when all the rows in a table are deleted.
You execute the commands:
Which two statements are true?
A. Thecreate usercommand fails if any role with the name Sidney exists in the database.
B. The userSidneycan connect to the database instance but cannot perform sort operations because no space quota is specified for thetemptablespace.
C. The userSidneyis created but cannot connect to the database instance because no profile is default.
D. The userSidneycan connect to the database instance but requires relevant privileges to create objects in theuserstablespace.
E. The userSidneyis created and authenticated by the operating system.
Examine the query and its output:
What might have caused three of the alerts to disappear?
A. The threshold alerts werecleared and transferred to DBA_ALERT_HISTORY.
B. An Automatic Workload Repository (AWR) snapshot was taken before the execution of the second query.
C. An Automatic Database Diagnostic Monitor (ADOM) report was generated before the execution of the secondquery.
D. The database instance was restarted before the execution of the second query.
Which two statements are true?
A. A role cannot be assigned external authentication.
B. A role can be granted to other roles.
C. A role can contain both system and object privileges.
D. The predefined resource role includes the unlimited_tablespace privilege.
E. All roles are owned by the sys user.
F. The predefined connect role is always automatically granted to all new usersat the time of their creation.
Identify three valid options for adding a pluggable database (PDB) to an existing multitenant container database (CDB).
A. Use the CREATE PLUGGABLE DATABASE statement to create a PDBusing the files from the SEED.
B. Use the CREATE DATABASE... ENABLE PLUGGABLE DATABASE statement to provision a PDB by copying file from the SEED.
C. Use the DBMS_PDB package to clone an existing PDB.
D. Use the DBMS_PDB package to plug an Oracle 12c non-CDB database into an existing CDB.
E. Use the DBMS_PDB package to plug an Oracle 11 g Release 2 (184.108.40.206.0) non-CDB database into an existing CDB.
Use the CREATE PLUGGABLE DATABASE statement to create a pluggable database (PDB).
This statement enables you to perform the following tasks:
- A) Create a PDB by using the seed as a template
Use the create_pdb_from_seed clause to create a PDB by using the seed in the multitenant container database (CDB) as a template. The filesassociated with the seed are copied to a new location and the copied files are then associated with the new PDB.
- C) Create a PDB by cloning an existing PDB
Use the create_pdb_clone clause to create a PDB by copying an existing PDB (the source PDB) and then plugging the copy into the CDB. The files associated with the source PDB are copied to a new location and the copied files are associated with the new PDB. This operation is called cloning a PDB.
The source PDB can be plugged in or unplugged. If plugged in, then the source PDB can be in the same CDB or in a remote CDB. If the source PDB is in a remote CDB, then a database link is used to connect to the remote CDB and copy the files.
- Create a PDB by plugging an unplugged PDB or a non-CDB into a CDB
Use the create_pdb_from_xml clause to plug an unplugged PDB or a non-CDB into a CDB, using an XML metadata file.
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.
- 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 setof 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.
- 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.
The following parameter are set for your Oracle 12c database instance:
You want to manage the SQL plan evolution task manually. Examine the following steps:
- Set the evolve task parameters.
- Create the evolve task by using the DBMS_SPM.CREATE_EVOLVE_TASK function.
- Implement the recommendations in the task by using the DBMS_SPM.IMPLEMENT_EVOLVE_TASK function.
- Execute the evolve task by using the DBMS_SPM.EXECUTE_EVOLVE_TASK function.
- 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
- Evolving SQL Plan Baselines
This function creates an advisor task to prepare the plan evolution of one or more plans for a specified SQLstatement. 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.
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 executiondescription. If not specified, the advisor generates the name, which is returned by the function.
This function implements all recommendations for an evolve task. Essentially, this function is equivalent to usingACCEPT_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.
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
- 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 anyof 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.
- 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.
Examine this command:
SQL> exec DBMS_STATS.SET_TABLE_PREFS (‘SH’, ‘CUSTOMERS’, ‘PUBLISH’, ‘false’);
Which three statements are true about the effect of this command?
A. Statistics collection is not done for the CUSTOMERS table when schema stats are gathered.
B. Statistics collection is not done for the CUSTOMERStable when database stats are gathered.
C. Any existing statistics for the CUSTOMERS table are still available to the optimizer at parse time.
D. Statistics gathered on the CUSTOMERS table when schema stats are gathered are stored as pending statistics.
E. Statistics gathered on the CUSTOMERS table when database stats are gathered are stored as pending statistics.
- SET_TABLE_PREFS Procedure
This procedure is used to set the statistics preferences of the specified table in thespecified schema.
Using Pending Statistics
Assume many modifications have been made to the employees table since the last time statistics were gathered. To ensure that the cost-based optimizer is still picking the best plan, statistics shouldbe gathered once again; however, the user is concerned that new statistics will cause the optimizer to choose bad plans when the current ones are acceptable. The user can do the following:
EXEC DBMS_STATS.SET_TABLE_PREFS('hr', 'employees', 'PUBLISH', 'false');
By setting the employees tables publish preference to FALSE, any statistics gather from now on will not be automatically published. The newly gathered statistics will be marked as pending.
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?
A. The import operation must be performed by a user on the target database by a user with theDATAPUMP_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 the 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 expdpoperation.
In this case we have run the impdp without performing any conversion if endian format is different then we have to first perform conversion.
Which two are true concerning a multitenant container database with three pluggable database?
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.
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.
- 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.
For example, suppose you have an environmentwith 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
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.
Which three statements are true concerning unplugging a pluggable database (PDB)?
A. The PDB must be open in read only mode.
B. The PDB must be dosed.
C. The unplugged PDBbecomes a non-CDB.
D. The unplugged PDB can be plugged into the same multitenant container database (CDB)
E. The unplugged PDB can be plugged into another CDB.
F. The PDB data files are automatically removed from disk.
B, not A:The PDB must be closed before unplugging it.
D: An unplugged PDB contains data dictionary tables, and some of the columns in these encode information in an endianness-sensitive way. There is no supported way to handle the conversion of such columns automatically. This means, quite simply, that an unplugged PDB cannot be moved across an endianness difference.
E (not F): To exploit the new unplug/plug paradigm for patching the Oracle version most effectively, the source and destination CDBs should share afilesystem so that the PDB’s datafiles can remain in place.
Examine the following command:
CREATE TABLE (prod_id number(4),
Prod_name varchar2 (20),
Quantity_on_hand number (3) INVISIBLE);
Which three statements are true about using an invisible column in the PRODUCTS table?
A. The %ROWTYPE attribute declarations in PL/SQL to access a row will not display the invisible column in the output.
B. The DESCRIBE commands in SQL *Plus will not display the invisible column in the output.
C. Referential integrity constraint cannot be set on the invisible column.
D. The invisible column cannot be made visible and can only be marked as unused.
E. A primary key constraint can be added on the invisible column.
AB: You can make individual table columns invisible. Any generic access of a table does not show the invisible columns in the table. For example, the following operations do not display invisible columns in the output:
- SELECT *FROM statements in SQL
- DESCRIBE commands in SQL*Plus
- ROWTYPE attribute declarations in PL/SQL
- Describes in Oracle Call Interface (OCI)
Not D: You can make invisible columns visible.
You can make a column invisible during table creation or when you add a column to a table, and you can later alter the table to make the same column visible.
You wish to enable an audit policy for all database users, except SYS, SYSTEM, and SCOTT.
You issue the following statements:
SQL> AUDIT POLICY ORA_DATABASE_PARAMETER EXCEPT SYS;
SQL> AUDIT POLICY ORA_DATABASE_PARAMETER EXCEPT SYSTEM;
SQL> AUDIT POLICY ORA_DATABASE_PARAMETER EXCEPT SCOTT;
For which database users is the audit policy now active?
A. All users except SYS
B. All users except SCOTT
C. All users except sys and SCOTT
D. All users except sys, system, and SCOTT
If you run multiple AUDIT statements on the same unified audit policy but specify different EXCEPT users, then Oracle Database usesthe last exception user list, not any of the users from the preceding lists. This means the effect of the earlier AUDIT POLICY... EXCEPT statements are overridden by the latest AUDIT POLICY... EXCEPT statement.
- The ORA_DATABASE_PARAMETER policyaudits commonly used Oracle Database parameter settings. By default, this policy is not enabled.
- You can use the keyword ALL to audit all actions. The following example shows how to audit all actions on the HR.EMPLOYEES table, except actions by user pmulligan.
Example Auditing All Actions on a Table
CREATE AUDIT POLICY all_actions_on_hr_emp_pol
ACTIONS ALL ON HR.EMPLOYEES;
AUDIT POLICY all_actions_on_hr_emp_pol EXCEPT pmulligan;
Successfully passing an important test can be a time consuming and monotonous process.