转:1Z0-042 记录(一)

3. You want to create a new optimized database for yourtransactional productionenvironmentto be used by a financial application. While creating the database, you want theOraclesoftware to take care of all basic settings to optimize the database performance. Which method would you use to achieve this objective?<?xml:namespace prefix = o ns = "urn:schemas-microsoft-com:office:office" />

A) Use the CREATE DATABASE.. command to create the database with Oracle-managed files.

B) Use the Database Configuration Assistant (DBCA) to create the database with Oracle-managed files.

C) Use Enterprise Manager to create a new database with the Online Transaction Processing (OLTP) option.

D) Use Database Configuration Assistant (DBCA) to create the database with Transaction Processing template.

E) Use the CREATE DATABASE.. command to create the database with Automatic Storage

Management (ASM) file system.

 

Editor’s note:the key of this question is transactional production environment（交易生产环境）.It seems to me that OLTP is needed. So ,you must create the OLTP db.

             Answer A/B/E does not meet the requirement of the question.

           Answer C is wrong.OEM cann’t create db.

 

5. A constraint in a table is defined with theINITIALLY IMMEDIATEclause. You executed the ALTER TABLE command with the ENABLE VALIDATE option to enable the constraint that was disabled. What are the two effects of this command? (Choose two.)

A) It fails if any existing rowviolates the constraint.

B) It does not validate the existingdatain the table. --alidate let oracle to check the existing data

C) It enables the constraint to be enforced at the end of each transaction.

D) It prevents insert, update, and delete operations on the table while the constraint is in the process of being enabled.

Editor’s note:The constraint of INITIALLY IMMEDIATE want oracle to check the contracint before and after thesql.

                       The constraint of enable validate want oracle to validate the data whitch may violates the constraint.

             So the answer is A/D

  Web site associated:

http://sns.linuxpk.com/space.php?uid=52196&do=blog&id=16032

http://space.itpub.net/21340813/viewspace-614897

http://www.itpub.net/viewthread.php?tid=4902

 

6. You received complaints about the degradation of SQL query performance. You identified top SQL queries that consume time. What would be your next step to find out recommendations about statistics collection and restructuring of the SQL statement to improve query performance?

A) run Segment Advisor

B) run SQL Tuning Advisor on top SQL statements

C) run the Automatic Workload Repository (AWR) report

D) run the Automatic Database Diagnostic Monitor (ADDM) on top SQL statements

Editor’s note: ADDM is like awr,it is using for monitor sql for system.not for top sql.

           B14211-- 12Automatic SQL Tuning (Database Performance Tuning Guide) will tell you how to use the sql tuning advisor and sql profiles.

Web site associated:

http://space.itpub.net/15720542/viewspace-631799 sql tunning adsivor的使用

http://www.hellodba.com/doc/oracle%2010g_addm_advisor.htm

http://asktom.oracle.com/pls/asktom/f?p=100:11:0::::P11_QUESTION_ID:61313086268493

 

10. Which statement regarding the contents of the V$PARAMETER view is true?

A) displays only the list of default values

B) displays only the list of all basic parameters

C) displays the currently in effect parameter values

D) displays only the list of all advanced parameters

E) displays the list of all the parameter files of a database

Editor’s note:V$PARAMETER displays information about the initialization parameters that are currently in effect for the session. A new session inherits parameter values from the instance-wide values displayed by the V$SYSTEM_PARAMETER view.

So,what’s the difference between v$parameter and v$system_parameter. If you execute the sql like that ‘alter session set parameter_name value.’ . You will see the difference with them by querying these two views.

 

16. You notice this warning in the alert log file:

ORA-19815: WARNING: db_recovery_file_dest_size of 3221225472 bytes is 100.00% used, and has 0 remaining bytes available.

What would you do to reclaim the used space in the Flash Recovery Area?

A) Back up the Flash Recovery Area.

B) Increase the retention time for the files.

C) Decrease the retention time for the files.

D) Manually delete all the archived log files from the Flash Recovery Area by using operating system (OS) commands.

Editor’s note:you can see the deail description of this error:

Cause: DB_RECOVERY_FILE_DEST is running out of disk space.

Action: One of the following:

1. Add disk space and increase DB_RECOVERY_FILE_DEST_SIZE.

2. Backup files to tertiary device usingRMAN.

3. Consider changing RMAN retention policy.

4. Consider changing RMAN archivelog deletion policy.

5. Delete files from recovery area using RMAN.

When you see the step 3,you will know why answer C is right.

 

18. Which two operations require undo data? (Choose two.)

A) committing a transaction

B) rolling back a transaction

C) recovering from failed transactions

D) recording a transaction to redo log files

E) rolling forward during instance recovery

Editor’s notes:answer C puzzle me. Transaction recover often happen when user cancel the transaction by manual, then smon have to be reclaimed unto segment.

 

57. Your database is configured with the following parameters related to SGA)

SGA_TARGET=256MB

SHARED_POOL_SIZE=32MB

DB_CACHE_SIZE=100MB

LARGE_POOL_SIZE=0

JAVA_POOL_SIZE=0

STREAMS_POOL_SIZE=0

Which two statements are true about the configuration? (Choose two.)

A) The SGA_TARGET value cannot be sized smaller than 100 MB.

B) The shared pool and the default buffer pool will not be sized bigger than 32 MB and 100 MB, respectively.

C) The shared pool and the default buffer pool will not be sized smaller than 32 MB and 100 MB, respectively.

D) 124 MB (256 minus 132) of memory is available for use by all the manually sized components.

E) 124 MB (256 minus 132) of memory is available for use by all the manually and automatically sized components.

Editor’s notes:the parameter of shared_pool_size and db_cache_size defined the smallest value of shared pool and buffer cache.When you define the sga_target’s value,shared pool size and buffer cache size will larger than the parameter defined.You can see it though v$sgainfo.

 

65. You executed the following command to start the database:

SQL> STARTUP

ORACLE instance started.

Total System Global Area 281018368 bytes

Fixed Size 789000 bytes

Variable Size 229635576 bytes

Database Buffers 50331648 bytes

Redo Buffers 262144 bytes

ORA-00205: error in identifying controlfile, check alert log for more info

Which view would you query at this stage to investigate this missing control file?

A) V$INSTANCE

B) V$CONTROLFILE

C) DBA_CONTROL_FILES

D) V$DATABASE_PROPERTIES

E) V$CONTROLFILE_RECORD_SECTION

Editor’s notes:v$controlfile lists the names of the control files.You can confirm whether the control files have broken by v$controlfile.status. INVALID if the name cannot be determined, which should not occur. Null if the name can be determined

V$CONTROLFILE_RECORD_SECTION displays information about the control file record sections.If control file grows too large,may be this view is very important.

 

69. You backed up the control file to trace. Which statement is true about the trace file generated?

A) The trace file is in binary format.

B) The trace file has a SQL script. to re-create the control file.

C) The trace file is a backup set created during the backup of the control file.

D) The trace file contains the instructions to manually re-create the control file.

E) The trace file is an image copy of the control file created during the backup of the control file.

Editor’s notes:There are two different ways to backup controlfiles.

One is:

ALTER DATABASE BACKUP CONTROLFILE TO TRACE (as filename);

This statement is used to create a trace file include sql statement for creating controlfile

Another is :

ALTER DATABASE BACKUP CONTROLFILE TO filename;

This statement is used to create binary file.it’s a backup controlfile for current controlfile.

 

78. Which two operations can be flashed back using the Flashback technology? (Choose two.)

A) DROP USER SMITH;

B) DROP TABLE EMPLOYEES;

C) DROP TABLESPACE USERS;

D) ALTER TABLE SALES_REP DROP PARTITION P1;

E) ALTER TABLE EMPLOYEES DROP COLUMN DESIG_ID;

Editor’s notes:The model answer must be wrong.flashback technology contains flashback query/flashback table/flashback database.A/B/D/E all can be flashback by using flashback technology.