Oracle Oracle Database 1Z0-060 Questions & Answers

• Question 161:

  Which three statements are true about adaptive SQL plan management?

  A. It automatically performs verification or evolves non-accepted plans, in COMPREHENSIVE mode when they perform better than existing accepted plans.

  B. The optimizer always uses the fixed plan, if the fixed plan exists in the plan baseline.

  C. It adds new, bettor plans automatically as fixed plans to the baseline.

  D. The non-accepted plans are automatically accepted and become usable by the optimizer if they perform better than the existing accepted plans.

  E. The non-accepted plans in a SQL plan baseline are automatically evolved, in COMPREHENSIVE mode, during the nightly maintenance window and a persistent verification report is generated.

  Correct Answer: ADE

  With adaptive SQL plan management, DBAs no longer have to manually run the verification or evolve process for non-accepted plans. When automatic SQL tuning is in COMPREHENSIVE mode, it runs a verification or evolve process for all SQL statements that have non-accepted plans during the nightly maintenance window. If the non-accepted plan performs better than the existing accepted plan (or plans) in the SQL plan baseline, then the plan is automatically accepted and becomes usable by the optimizer. After the verification is complete, a persistent report is generated detailing how the non-accepted plan performs compared to the accepted plan performance. Because the evolve process is now an AUTOTASK, DBAs can also schedule their own evolve job at end time.

  Note:

  *

  The optimizer is able to adapt plans on the fly by predetermining multiple subplans for portions of the plan.

  *

  Adaptive plans, introduced in Oracle Database 12c, enable the optimizer to defer the final plan decision for a statement until execution time. The optimizer instruments its chosen plan (the default plan) with statistics collectors so that it can detect at runtime, if its cardinality estimates differ greatly from the actual number of rows seen by the operations in the plan. If there is a significant difference, then the plan or a portion of it will be automatically adapted to avoid suboptimal performance on the first execution of a SQL statement.

• Question 162:

  You are planning the creation of a new multitenant container database (CDB) and want to store the ROOT and SEED container data files in separate directories.

  You plan to create the database using SQL statements.

  Which three techniques can you use to achieve this? (Choose three.)

  A. Use Oracle Managed Files (OMF).

  B. Specify the SEED FILE_NAME_CONVERT clause.

  C. Specify the PDB_FILE_NAME_CONVERT initialization parameter.

  D. Specify the DB_FILE_NAME_CONVERT initialization parameter.

  E. Specify all files names in the CREATE DATABASE statement without using Oracle managed Files (OMF).

  Correct Answer: ABC

  You must specify the names and locations of the seed's files in one of the following ways:

  *

  (A) Oracle Managed Files

  *

  (B) The SEED FILE_NAME_CONVERT Clause

  *

  (C) The PDB_FILE_NAME_CONVERT Initialization Parameter

• Question 163:

  You are about to plug a multi-terabyte non-CDB into an existing multitenant container database (CDB).

  The characteristics of the non-CDB are as follows: Version: Oracle Database 11g Release 2 (11.2.0.2.0) 64-bit Character Set: AL32UTF8 National Character Set: AL16UTF16 O/S: Oracle Linux 6 64-bit

  The characteristics of the CDB are as follows: Version: Oracle Database 12c Release 1 64-bit Character Set: AL32UTF8 National Character Set: AL16UTF16 O/S: Oracle Linux 6 64-bit

  Which technique should you use to minimize down time while plugging this non-CDB into the CDB?

  A. Transportable database

  B. Transportable tablespace

  C. Data Pump full export/import

  D. The DBMS_PDB package

  E. RMAN

  Correct Answer: B

  Transportable tablespaces were introduced in Oracle 8i to allow whole tablespaces to be copied between databases in the time it takes to copy the datafiles. It is supported in Oracle 11g.

  Incorrect Answers:

  A: Using Transportable database with the "FULL=Y TRANSPORTABLE=ALWAYS VERSION=12" parameters allows you to plug in an 11.2.0.3 or later non-CDB 11g database, not an 11.2.0.2.0 database.

  D: The DBMS_PDB package allows you to generate an XML metadata file from a non-CDB 12c database. This allows the non-CDB to be plugged in as a PDB into an existing CDB. However, the non-CBD is an 11g (11.2.0.2.0) database.

• Question 164:

  Your database supports an online transaction processing (OLTP) application. The application is undergoing some major schema changes, such as addition of new indexes and materialized views. You want to check the impact of these changes on workload performance.

  What should you use to achieve this?

  A. Database replay

  B. SQL Tuning Advisor

  C. SQL Access Advisor

  D. SQL Performance Analyzer

  E. Automatic Workload Repository compare reports

  Correct Answer: D

  You can use the SQL Performance Analyzer to analyze the SQL performance impact of any type of system change. Examples of common system changes include: Database upgrades Configuration changes to the operating system, hardware, or database Database initialization parameter changes Schema changes, such as adding new indexes or materialized views Gathering optimizer statistics SQL tuning actions, such as creating SQL profiles

  References: http://docs.oracle.com/cd/B28359_01/server.111/b28318/intro.htm#CNCPT961

• Question 165:

  An administrator account is granted the CREATE SESSION and SET CONTAINER system privileges.

  A multitenant container database (CDB) instant has the following parameter set:

  THREADED_EXECUTION = FALSE

  Which four statements are true about this administrator establishing connections to root in a CDB that has been opened in read only mode? (Choose four.)

  A. You can connect as a common user by using the CONNECT statement.

  B. You can connect as a local user by using the CONNECT statement.

  C. You can connect by using easy connect.

  D. You can connect by using OS authentication.

  E. You can connect by using a Net Service name.

  F. You can connect as a local user by using the SET CONTAINER statement.

  Correct Answer: ACDE

  http://docs.oracle.com/database/121/ADMIN/cdb_admin.htm

• Question 166:

  You upgraded your database from pre-12c to a multitenant container database (CDB) containing pluggable databases (PDBs).

  Examine the query and its output:

  

  Which two tasks must you perform to add users with SYSBACKUP, SYSDG, and SYSKM privilege to the password file?

  A. Assign the appropriate operating system groups to SYSBACKUP, SYSDG, SYSKM.

  B. Grant SYSBACKUP, SYSDG, and SYSKM privileges to the intended users.

  C. Re-create the password file with SYSBACKUP, SYSDG, and SYSKM privilege and the FORCE argument set to No.

  D. Re-create the password file with SYSBACKUP, SYSDG, and SYSKM privilege, and FORCE arguments set to Yes.

  E. Re-create the password file in the Oracle Database 12c format.

  Correct Answer: BD

  * orapwd

  / You can create a database password file using the password file creation utility, ORAPWD.

  The syntax of the ORAPWD command is as follows:

  orapwd FILE=filename [ENTRIES=numusers] [FORCE={y|n}] [ASM={y|n}]

  [DBUNIQUENAME=dbname] [FORMAT={12|legacy}] [SYSBACKUP={y|n}] [SYSDG={y|n}]

  [SYSKM={y|n}] [DELETE={y|n}] [INPUT_FILE=input-fname]

  force - whether to overwrite existing file (optional),

  * v$PWFILE_users / 12c: V$PWFILE_USERS lists all users in the password file, and indicates whether the user has been granted the SYSDBA, SYSOPER, SYSASM, SYSBACKUP, SYSDG, and SYSKM privileges.

  / 10c: sts users who have been granted SYSDBA and SYSOPER privileges as derived from the password file.

  ColumnDatatypeDescription USERNAMEVARCHAR2(30)The name of the user that is contained in the password file SYSDBAVARCHAR2(5)If TRUE, the user can connect with SYSDBA privileges SYSOPERVARCHAR2(5)If TRUE, the user can connect with SYSOPER privileges

  Incorrect Answers:

  E: The format of the v$PWFILE_users file is already in 12c format.

• Question 167:

  An application accesses a small lookup table frequently. You notice that the required data blocks are getting aged out of the default buffer cache.

  How would you guarantee that the blocks for the table never age out?

  A. Configure the KEEP buffer pool and alter the table with the corresponding storage clause.

  B. Increase the database buffer cache size.

  C. Configure the RECYCLE buffer pool and alter the table with the corresponding storage clause.

  D. Configure Automata Shared Memory Management.

  E. Configure Automatic Memory Management-

  Correct Answer: A

  Schema objects are referenced with varying usage patterns; therefore, their cache behavior may be quite different. Multiple buffer pools enable you to address these differences. You can use a KEEP buffer pool to maintain objects in the buffer cache and a RECYCLE buffer pool to prevent objects from consuming unnecessary space in the cache. When an object is allocated to a cache, all blocks from that object are placed in that cache. Oracle maintains a DEFAULT buffer pool for objects that have not been assigned to one of the buffer pools.

• Question 168:

  You conned using SQL Plus to the root container of a multitenant container database (CDB) with SYSDBA privilege.

  The CDB has several pluggable databases (PDBs) open in the read/write mode.

  There are ongoing transactions in both the CDB and PDBs.

  What happens alter issuing the SHUTDOWN TRANSACTIONAL statement?

  A. The shutdown proceeds immediately. The shutdown proceeds as soon as all transactions in the PDBs are either committed or rolled hack.

  B. The shutdown proceeds as soon as all transactions in the CDB are either committed or rolled back.

  C. The shutdown proceeds as soon as all transactions in both the CDB and PDBs are either committed or rolled back.

  D. The statement results in an error because there are open PDBs.

  Correct Answer: B

  * SHUTDOWN [ABORT | IMMEDIATE | NORMAL | TRANSACTIONAL [LOCAL]]

  Shuts down a currently running Oracle Database instance, optionally closing and dismounting a database. If the current database is a pluggable database, only the pluggable database is closed. The consolidated instance continues to run.

  Shutdown commands that wait for current calls to complete or users to disconnect such as SHUTDOWN NORMAL and SHUTDOWN TRANSACTIONAL have a time limit that the SHUTDOWN command will wait. If all events blocking the shutdown have not occurred within the time limit, the shutdown command cancels with the following message:

  ORA-01013: user requested cancel of current operation

  * If logged into a CDB, shutdown closes the CDB instance.

  To shutdown a CDB or non CDB, you must be connected to the CDB or non CDB instance that you want to close, and then enter

  SHUTDOWN

  Database closed.

  Database dismounted.

  Oracle instance shut down.

  To shutdown a PDB, you must log into the PDB to issue the SHUTDOWN command.

  SHUTDOWN

  Pluggable Database closed.

  Note:

  * Prerequisites for PDB Shutdown

  When the current container is a pluggable database (PDB), the SHUTDOWN command can only be used if:

  The current user has SYSDBA, SYSOPER, SYSBACKUP, or SYSDG system privilege.

  The privilege is either commonly granted or locally granted in the PDB.

  The current user exercises the privilege using AS SYSDBA, AS SYSOPER, AS SYSBACKUP, or AS SYSDG at connect time.

  To close a PDB, the PDB must be open.

• Question 169:

  You notice a performance change in your production Oracle 12c database. You want to know which change caused this performance difference.

  Which method or feature should you use?

  A. Compare Period ADDM report

  B. AWR Compare Period report

  C. Active Session History (ASH) report

  D. Taking a new snapshot and comparing it with a preserved snapshot

  Correct Answer: A

• Question 170:

  You want to capture column group usage and gather extended statistics for better cardinality estimates for the CUSTOMERS table in the SH schema.

  Examine the following steps:

  1.

  Issue the SELECT DBMS_STATS.CREATE_EXTENDED_STATS (`SH', `CUSTOMERS') FROM dual statement.

  2.

  Execute the DBMS_STATS.SEED_COL_USAGE (null, `SH', 500) procedure.

  3.

  Execute the required queries on the CUSTOMERS table.

  4.

  Issue the SELECT DBMS_STATS.REPORT_COL_USAGE (`SH', `CUSTOMERS') FROM dual statement.

  Identify the correct sequence of steps.

  A. 3, 2, 1, 4

  B. 2, 3, 4, 1

  C. 4, 1, 3, 2

  D. 3, 2, 4, 1

  Correct Answer: B

  Step 1 (2). Seed column usage Oracle must observe a representative workload, in order to determine the appropriate column groups. Using the new procedure DBMS_STATS.SEED_COL_USAGE, you tell Oracle how long it should observe the workload. Step 2: (3) You don't need to execute all of the queries in your work during this window. You can simply run explain plan for some of your longer running queries to ensure column group information is recorded for these queries. Step 3. (1) Create the column groups At this point you can get Oracle to automatically create the column groups for each of the tables based on the usage information captured during the monitoring window. You simply have to call the DBMS_STATS.CREATE_EXTENDED_STATS function for each table.This function requires just two arguments, the schema name and the table name. From then on, statistics will be maintained for each column group whenever statistics are gathered on the table.

  Note:

  *

  DBMS_STATS.REPORT_COL_USAGE reports column usage information and records all the SQL operations the database has processed for a given object.

  *

  The Oracle SQL optimizer has always been ignorant of the implied relationships between data columns within the same table. While the optimizer has traditionally analyzed the distribution of values within a column, he does not collect value- based relationships between columns.

  *

  Creating extended statisticsHere are the steps to create extended statistics for related table columns withdbms_stats.created_extended_stats: 1 - The first step is to create column histograms for the related columns.2 ?Next, we run dbms_stats.create_extended_stats to relate the columns together. Unlike a traditional procedure that is invoked via an execute ("exec") statement, Oracle extended statistics are created via a select statement.