1z0-043 lesson 7 Dealing with Database Corruption

1z0-043 lesson 7

完成!!!

是否显示我的答案
是否显示书上的答案和我的注释


1.
5、You are performing a block media recovery on the tools01.dbf data file in the SALES database using RMAN. Which two statements are correct in this scenario? (Choose two.)
A. You must ensure that the SALES database is mounted or open.
B. You must restore a backup control file to perform a block media recovery.
C. You must take the tools01.dbf data file offline before you start a block media recovery.
D. You must put the database in NOARCHIVELOG mode to perform a block media recovery.
E. You can perform only a complete media recovery of individual blocks, point-in-time recovery of individual data blocks is not supported.

AE

AE

教材上没说
见Block Media Recovery with RMAN:
"You must have a full RMAN backup. Incremental backups are not used by block media recovery. Proxy backups are also not used by block media recovery. Only full backups and archived log files are used."

2.
11、Your database is open and running in ARCHIVELOG mode. You take RMAN full backups every Sunday night. On Monday morning, while querying the user1.employees table, you receive the following error message:
ORA-01578: ORACLE data block corrupted (file # 5, block # 51)
ORA-01110: data file 5:'/u01/app/oracle/oradata/orcl/example01.dbf'
You need to rectify the corruption while ensuring the following:
The data file should remain online.
The mean time to recover (MTTR) should be minimal.
You are not using a backup control file and all the archived logs are accessible.
Which option would you choose?
A. flash back the corrupted blocks
B. use the DBMS_REPAIR package
C. use the RMAN TSPITR command
D. use the RMAN BLOCKRECOVER command
E. use the RESTORE DATABASE and RECOVER DATABASE commands
F. investigate the time at which the corruption occurred and perform a point-in-time recovery

D

D

B.DBMS_REPIAR不一定能恢复?

3.
38. The DB_BLOCK_CHECKING initialization parameter is set to TRUE. What would be the result of this setting on the data blocks being written to the datafiles, every time the DBWn writes?
A. The Oracle database will check all data blocks by going through the data on each block, making sure the data is self-consistent.
B. The DBWn and the direct loader will calculate a checksum and store it in the cache header of every data block when writing it to disk.
C. The Oracle database will check data blocks belonging to the SYSTEM tablespace only, by going through the data on each block, making sure the data is self-consistent.
D. The Oracle database will check data blocks belonging to the SYSAUX tablespace only, by going through the data on each block, making sure the data is self-consistent.
E. The Oracle database will check data blocks in the SYSTEM and SYSAUX tablespaces only, by going through the data on each block, making sure the data is self-consistent.

A

A

教材7-12
"When DB_BLOCK_CHECKING is set to TRUE, the Oracle database performs block checking for all data blocks. The Oracle database checks a block by reading the data on the block and making sure that it is self-consistent."

4.
53. There was media failure and you need to check the data files for any block corruption. Which option would you use to create a report on any corruptions found within the database?
A. the DBNEWID utility
B. the DBVERIFY utility
C. the ANALYZE command
D. the RMAN REPORT command
E. the RMAN CROSSCHECK command
F. the CHECK_OBJECT procedure of the DBMS_REPAIR package

B

B

教材7-9

5.
85. A data file become corrupted in your database due to bad sectors on the disk. Because of corruption, you lost all the important tables in that data file. Which method would you use for recovery?
A. Flash back all the tables in the data file, one by one.
B. Restore the data file to a new location and perform a media recovery.
C. Flash back the database, there is no need to restore the data file.
D. Restore the data file from the most recent backup and flash the database.

B

B

恢复数据文件,然后媒体恢复

6.
88. You execute the following RMAN command in the order shown below: BACKUP VALIDATE DATABASE; BLOCKRECOVER CORRUPTION LIST; What will these commands do?
A. Create a backup of the database and recover all corrupted blocks found in the backup.
B. Run a backup validation and list all the logically corrupt blocks as well as physically corrupt blocks in the database.
C. Run a backup validation to populate V$COPY_CORRUPTION view, and then list any corrupt blocks recorded in the view.
D. Run a backup validation to populate V$DATABASE_BLOCK_CORRUPTION view, and then repair any corrupt blocks recorded in the view.
E. Run a backup validation, repair any corrupt blocks found during the validation process, and then update V$DATABASE_BLOCK_CORRUPTION view to indicate which corrupt blocks have been repaired.

B

D

教材7-25
"By using the CORRUPTION LIST clause, you can recover blocks that are listed in V$DATABASE_BLOCK_CORRUPTION. This view is populated during a backup operation, as corrupt blocks are encountered. If the backup encounters more than the tolerated number of corrupt blocks, then the view is not populated at all. You should then run the BACKUP…VALIDATE command to fully populate this view with a record of all corrupt blocks."

7.
96. You need to check the EMP_EAST partition in the EMPLOYEES table for physical corruptions. You also need to verify that the rows belong to the correct partition. Which option could you use?
A. LogMiner
B. The DBNEWID utility
C. The DBVERIFY utility
D. The ANALYZE command
E. The RMAN REPORT command
F. The RMAN CROSSCHECK command.
G. The RMAN BLOCKRECOVER command.

D

D

教材7-11
"For partitioned tables, ANALYZE also verifies that the row belongs to the correct partition. If the row does not collate correctly, the row ID is inserted in the INVALID_ROWS table."

8.
120. What are the two advantages of RMAN Block Media Recovery (BMR) over file-level recovery? (Choose two)
A. BMR lowers the mean time to recover (MTTR).
B. BMR supports point-in-time recovery of individual data blocks.
C. BMR enables you to use incremental backups for block recovery.
D. BMR enables recovery even when the database is not mounted or open.
E. BMR enables you to use proxy backups to perform block media recovery.
F. BMR enables increased availability of data during recovery because the data file requires a recovery can remain online.

AF

AF

教材7-21

9.
141. The DB_BLOCK_CHECKING initialization parameter is set to FALSE. What level of block checking would be performed?
A. The Oracle database will not perform block checking for any of the data blocks.
B. The Oracle database will perform block checking for the default permanent tablespace only.
C. The Oracle database will perform block checking for the data blocks in all user tablespaces.
D. The Oracle database will perform block checking for the data blocks in the SYSTEM tablespace only.
E. The Oracle database will perform block checking for the data blocks in the SYSTEM and SYSAUX tablespaces.

A

D

教材7-12
"The default value is FALSE, which, for backward compatibility, is equivalent to OFF. Even if this is turned off, block checking for the SYSTEM tablespace is always turned on."

10.
169. The EMPLOYEES table is stored in the USERS tablespace. You need to check if the EMPLOYEES table is affected by the block corruption found in the USERS tablespace. Which option would you use?
A. the RMAN LIST command
B. the DBNEWID utility
C. the RMAN REPORT command
D. the RMAN BLOCKRECOVER command
E. the RMAN CROSSCHECK command
F. the ANALYZE command

F

F

别的不能检查表

=====
11.
24. DB_BLOCK_CHECKING performs checksums on modified blocks only on what database objects?
A. All database objects by default
B. All database objects if DB_BLOCK_CHECKING is TRUE
C. All non-system tablespace objects if DB_BLOCK_CHECKING is FALSE
D. All system tablespace objects only if DB_BLOCK_CHECKING is TRUE

B

24. B. DB_BLOCK_CHECKING reports on all database objects if DB_BLOCK_CHECKING is TRUE. See Chapter 7 for more information.

教材7-12

12.
25. What is the correct syntax for performing a block media recovery for corrupt blocks in datafile 4 and 5 with blocks 5 and 6, respectively?
A. RMAN> blockrecover datafile 4-5 block 5-6;
B. SQL> blockrecover datafile 4 and 5 block 5 and 6;
C. RMAN> blockrecover datafile 4 block 5;
RMAN> blockrecover datafile 5 block 6;
D. RMAN> blockrecover datafile 4 and 5 block 5 and 6;

C

25. C. The correct syntax to perform a block media recovery for corrupt blocks in two datafiles is to execute multiple BLOCKRECOVER commands, one for each datafile and block. See Chapter 7 for more information.

教材7-23

13.
26. What is the name of the DBMS_REPAIR procedure used to identify index entries that point to corrupt data blocks?
A. DUMP_ORPHAN_KEYS
B. DUMP_ORPHAN_KEY
C. DUMP_CHILD_KEYS
D. DUMP_ORPHANS_KEYS

A
?

26. A. The DUMP_ORPHAN_KEYS is designed to identify index entries that point to corrupt data blocks. See Chapter 7 for more information.

教材7-20

14.
27. What type of backup should not be used to support RMAN block media recovery (BMR)?
A. Any incremental backup should not be used to support BMR.
B. Only a differential incremental backup should not be used to support BMR.
C. Full backups should not be used to support BMR.
D. Only a cumulative incremental backup should not be used to support BMR.

A
不知道

27. A. All incremental backups will not support BMR because they contain only changed blocks. See Chapter 7 for more information.

见第1题

=====
15.
1. What activity is responsible for causing most block corruption?
A. Human errors that introduce bugs caused by hardware, software, or firmware
B. Memory errors written to disk
C. Random I/O errors written to disk
D. A bad transaction that updates many tables

B
不知道

1. A. Most block corruption is caused by human error introducing bugs with new hardware, software, or firmware changes.

大多数错误是人为导致的

16.
2. What is the most common way of detecting block corruption in the database?
A. Monitoring the operating system log files
B. Monitoring the application log files
C. Monitoring the ALERT.LOG database log
D. Monitoring the ALERT.LOG and associated trace files

D
C也行吧?

2. D. Monitoring the ALERT.LOG and associated trace files is the best method for detecting block corruption in the database.

C.只看告警日志也行呀

17.
3. What is the correct command to analyze the EMPLOYEE table in the schema owned by user TEST?
A. ANALYZE INDEX EMPLOYEE VALIDATE STRUCTURE
B. ANALYZE TABLE TEST.EMPLOYEE VALIDATE STRUCTURE
C. ANALYZE TABLE EMPLOYEE VALIDATE STRUCTURE
D. ANALYZE INDEX TEST.EMPLOYEE VALIDATE STRUCTURE

C

3. B. If the ANALYZE command is being run by a DBA account, you need to prefix the table name with the schema owner.

就是B. 不该错的呀

18.
4. Which of the following is the most correct statement about what the ANALYZE command does?
A. The ANALYZE command identifies the object and blocks where corruption exists.
B. The ANALYZE command identifies the objects where corruption exists.
C. The ANALYZE command identifies the table where corruption exists.
D. The ANALYZE command identifies the index and the block where corruption exists.

B
不理解

4. B. The ANALYZE command determines which object has corrupted indexes or tables, because the command returns an error if the statement does not process completely. The ANALYZE command does not identify which block is corrupt.

不能查出具体是哪个数据块坏了
VALIDATE STRUCTURE

19.
5. The DBVERIFY utility reports output about corruption in which manner?
A. The DBVERIFY utility identifies the amount of corrupt objects, not the amount of blocks in a table.
B. The DBVERIFY utility identifies the amount of corrupt blocks, not the amount of objects in a datafile.
C. The DBVERIFY utility identifies the amount of corrupt pages, not the amount of blocks in a datafile.
D. The DBVERIFY utility identifies the amount of corrupt pages, not the amount of blocks in the database.

C

5. C. The DBVERIFY utility uses the term pages instead of blocks. The DBVERIFY utility determines the amount of corrupt pages in a datafile.

单位是页
教材7-9

20.
6. Which of the following is a correct statement about the DBVERIFY utility?
A. The DBVERIFY utility can be executed only on online datafiles.
B. The DBVERIFY utility can be executed on online datafiles and offline datafiles.
C. The DBVERIFY utility can be executed only on offline datafiles.
D. The DBVERIFY utility can be executed only on online datafiles and offline tablespaces.

B

6. B. The DBVERIFY utility can be used on online and offline datafiles.

教材7-8
"DBVERIFY is an external command-line utility that performs a physical data structure integrity check on a database that is offline or online."

21.
7. What is the correct syntax for using the DBVERIFY utility to write to a file and to verify the DATA tablespace with a 4k database block size?
A. dbv blocksize=4096 file=data01.dbf logfile=c:\temp\data01.log
B. dbv blocksize=4096 file=user01.dbf logfile=c:\temp\data01.log
C. dbv file=data01.dbf blocksize=4k logfile=c:\temp\data01.log
D. dbverify blocksize=4096 file=data01.dbf logfile=c:\temp\data01.log

A

7. A . The correct syntax for the DBVERIFY utility to write the output to a log and specify a 4k block size is as follows: dbv blocksize=4096 file=data01.dbf logfile=c:\temp\data01.log.

教材7-8

22.
8. The DB_BLOCK_CHECKING initialization parameter needs be enabled to verify what objects?
A. Objects stored in the default tablespace of the SYS user
B. Objects stored in the default tablespace of any application owner
C. Objects stored in the default tablespace of the SCOTT user
D. Objects stored in the default tablespace of the HR user

B
没看懂

8. A. DB_BLOCK_CHECKING is enabled for the SYSTEM tablespace by default. The SYS user default tablespace is SYSTEM.

什么乱七八糟的

DB_BLOCK_CHECKING和DB_BLOCK_CHECKSUM默认的都是检查SYSTEM表空间
DB_BLOCK_CHECKING
DB_BLOCK_CHECKSUM

23.
9. What statement best describes DB_BLOCK_CHECKING?
A. DB_BLOCK_CHECKING is a utility that performs checksums on blocks every time the block is modified.
B. DB_BLOCK_CHECKING is a database parameter that causes the Oracle to perform checksums on blocks every time the block is modified.
C. DB_BLOCK_CHECKING is a command that performs checksums on blocks every time the checkpoint process occurs.
D. DB_BLOCK_CHECKING is a database parameter that performs checksums on blocks every time the database checkpoint occurs.

B
修改时才检查?

9. B. DB_BLOCK_CHECKING is a database parameter that causes Oracle to perform checksums on blocks every time the block is modified.

是的
教材7-12
"The more updates or inserts being executed, the more expensive it is to turn on block checking."

24.
10. How should you use the DBMS_REPAIR package to build a REPAIR_TABLE for the DATA tablespace that can help the diagnosis of corrupt rows in a table in that tablespace?
A.

declare
begin
  dbms_repair.admin_table(
    table_name => 'REPAIR_TABLE',
    table_type => dbms_repair.repair_table,
    action => dbms_repair.create_action,
    tablespace => 'DATA01');
end;
/

B.

declare
begin
  dbms_repair.admin_tables(
    table_name => 'REPAIR_TABLE',
    table_type => dbms_repair.repair_table,
    action => dbms_repair.create_action,
    tablespace => 'DATA');
end;
/

C.

declare
begin
  dbms_repair.admin_table(
    table_name => 'REPAIR_TABLE',
    table_type => dbms_repair.repair_tables,
    action => dbms_repair.create_action,
    tablespace => 'DATA');
end;
/

D.

declare
begin
  dbms_repair.admin_tables(
    table_name => 'REPAIR_TABLE',
    table_type => dbms_repair.repair_table,
    action => dbms_repair.create_action,
    tablespace => 'DATA');
end;
/

A
猜的
BD是一样的?

10. B. The correct use of the DBMS_REPAIR package on the DATA tablespace is to use the ADMIN_TABLES procedure with the following parameters:

declare
begin
  dbms_repair.admin_tables(
    table_name => 'REPAIR_TABLE',
    table_type => dbms_repair.repair_table,
    action => dbms_repair.create_action,
    tablespace => 'DATA');
end;
/

破题,BD一样
教材7-17

25.
11. How should you use the DBMS_REPAIR package to verify REPAIR BLOCK COUNT and load REPAIR_TABLE for the EMPLOYEE table in the SCOTT schema with information of the object and block that is corrupt in the tablespace?
A.

set serveroutput on size 100000;
declare
  rpr_count int;
begin
  rpr_count := 0;
  dbms_repair.check_objects(
    schema_name => 'SCOTT',
    object_name => 'EMPLOYEE',
    repair_table_name => 'REPAIR_TABLE',
    corrupt_count => rpr_count);
  dbms_output.put_line('repair block count: '||to_char(rpr_count));
end;

B.

set serverout on size 100000;
declare
  rpr_count int;
begin
  rpr_count := 0;
    dbms_repair.check_objects(
    schema_name => 'SCOTT',
    object_name => 'EMPLOYEE',
    repair_table_name => 'REPAIR_TABLESPACE',
    corrupt_count => rpr_count);
  dbms_output.put_line('repair block count: '||to_char(rpr_count));
end;

C.

set serveroutput on size 100000;
declare
  rpr_count int;
begin
  rpr_count := 0;
  dbms_repair.check_object(
    schema_name => 'SCOTT',
    object_name => 'EMPLOYEE',
    repair_table_name => 'REPAIR_TABLE',
    corrupt_count => rpr_count);
  dbms_output.put_line('repair block count: '||to_char(rpr_count));
end;

D.

set serverout on size 100000;
declare
  rpr_count int;
begin
  rpr_count := 0;
  dbms_repair.check_object(
    schema_name => 'SCOTT',
    object_name => 'EMPLOYEE',
    repair_table_name => 'REPAIR_TABLE',
    corrupt_count => rpr_count);
  dbms_output.put_line('repair block count: '||to_char(rpr_count));
end;

C
CD一样?什么破题

11. C. The DBMS_REPAIR package must be used with the CHECK_OBJECT procedure. If you want to verify REPAIR BLOCK COUNT, you must have SET SERVEROUTPUT ON SIZE. The following is the correct PL/SQL syntax for the DBMS_REPAIR package:

set serveroutput on size 100000;
declare
  rpr_count int;
begin
  rpr_count := 0;
  dbms_repair.check_object(
    schema_name => 'SCOTT',
    object_name => 'EMPLOYEE',
    repair_table_name => 'REPAIR_TABLE',
    corrupt_count => rpr_count);
  dbms_output.put_line('repair block count: '||to_char(rpr_count));
end;

破题
教材7-17

26.
12. What could be impacted by the DBMS_REPAIR package being used on a table?
A. A table related by a foreign key and primary key to the table repaired by the DBMS_REPAIR package could become unusable.
B. A trigger on the table repaired by the DBMS_REPAIR package could introduce logical corruption.
C. An index related to the table repaired by the DBMS_REPAIR package could become out of sync with the repaired table.
D. All of the above.

D

12. D. Referential integrity constraints on related tables can be broken, indexes can become out of sync with the table data, and triggers on a table can cause logical corruption if they are not well understood when using the DBMS_REPAIR package on a table.

见Task 2: Evaluate the Costs and Benefits of Using DBMS_REPAIR
"It is also possible that referential integrity constraints are broken when blocks are marked corrupt. If this occurs, then disable and reenable the constraint; any inconsistencies are reported. After fixing all problems, you should be able to reenable the constraint.

Logical corruption can occur when there are triggers defined on the table. For example, if rows are reinserted, should insert triggers be fired or not? You can address these issues only if you understand triggers and their use in your installation.

If indexes and tables are not synchronized, then execute the DUMP_ORPHAN_KEYS procedure to obtain information from the keys that might be useful in rebuilding corrupted data. Then issue the ALTER INDEX...REBUILD ONLINE statement to synchronize the table with its indexes."

27.
13. How should you use the DBMS_REPAIR package to identify problems with a primary key index on a corrupt table in the SCOTT schema with the EMPLOYEE_PK index? (Choose all that apply.)
A.

declare
  orph_count int;
begin
  orph_count:= 0;
  dbms_repair.dump_child_keys (
    schema_name => 'SCOTT',
    object_name => 'EMPLOYEE_PK',
    object_type => dbms_repair.index_object,
    repair_table_name => 'REPAIR_TABLE',
    orphan_table_name => 'ORPHAN_KEY_TABLE',
    key_count => orph_count);
  dbms_output.put_line('orphan-index entries: ' || to_char(orph_count));
end;
/

B.

declare
  orph_count int;
begin
  orph_count:= 0;
  dbms_repair.dump_orphan_key (
    schema_name => 'SCOTT',
    object_name => 'EMPLOYEE_PK',
    object_type => dbms_repair.index_object,
    repair_table_name => 'REPAIR_TABLE',
    orphan_table_name => 'ORPHAN_KEY_TABLE',
    key_count => orph_count);
  dbms_output.put_line('orphan-index entries: ' || to_char(orph_count));
end;
/

C.

declare
  orph_count int;
begin
  orph_count:= 0;
  dbms_repair.dump_orphan_keys (
    schema_name => 'SCOTT',
    object_name => 'EMPLOYEE_PK',
    object_type => dbms_repair.index_object,
    repair_table_name => 'REPAIR_TABLE',
    orphan_table_name => 'ORPHAN_KEY_TABLE',
    key_count => orph_count);
  dbms_output.put_line('orphan-index entries: ' || to_char(orph_count));
end;
/

D.

declare
  orph_count int;
begin
  orph_count:= 0;
  dbms_repair.dump_orphan_key (
    schema_name => 'SCOTT',
    object_name => 'EMPLOYEE_PK',
    object_type => dbms_repair.index_object,
    repair_table_name => 'REPAIR_TABLE',
    orphan_table_name => 'ORPHAN_KEY_VIEW',
    key_count => orph_count);
  dbms_output.put_line('orphan-index entries: ' || to_char(orph_count));
end;
/

C
猜的

13. C. The DBMS_REPAIR package can be used to identify problems with a primary index by identifying orphaned keys in the index as they relate to the table being repaired for corruption. The correct usage of the DBMS_REPAIR.DUMP_ORPHANED_KEYS package procedure is as follows:

declare
  orph_count int;
begin
  orph_count:= 0;
  dbms_repair.dump_orphan_keys (
    schema_name => 'SCOTT',
    object_name => 'EMPLOYEE_PK',
    object_type => dbms_repair.index_object,
    repair_table_name => 'REPAIR_TABLE',
    orphan_table_name => 'ORPHAN_KEY_TABLE',
    key_count => orph_count);
  dbms_output.put_line('orphan-index entries: ' || to_char(orph_count));
end;
/

教材7-20

28.
14. What table can you query to identify the block that is corrupt?
A. DBA_CORRUPT_BLOCKS
B. REPAIR_TABLE
C. DBA_REPAIR_TABLE
D. CORRUPT_BLOCKS_TABLE

A
不知道

14. B. REPAIR_TABLE will show OBJECT_NAME, BLOCK_ID, and if the block is MARKED_CORRUPT.

必须叫REPAIR_TABLE啊, 别的不可以吗?

29.
15. When determining how to resolve block corruption, what should you keep in mind?
A. The tables where the corruption is located
B. The block or blocks in the corrupt table
C. The extent of the corruption in the table or tables
D. The tables and indexes where the corruption is located

B
不解

15. C. When determining how to resolve block corruption, you should determine the extent of the corruption first. Is the corruption limited to a few blocks or is it widespread?

还是不解, 为啥不能是表级或块级?

30.
16. How should you use the DBMS_REPAIR package to rebuild freelists on a corrupt table?
A.

declare
begin
  dbms_repair.rebuild_freelist (
    schema_name => 'SCOTT',
    object_name => 'EMPLOYEE',
    object_type => dbms_repair.table_object);
end;
/

B.

declare
begin
  dbms_repair.rebuild_freelists (
    schema_name => 'SCOTT',
    object_name => 'EMPLOYEE',
    object_type => dbms_repair.object_table);
end;
/

C.

declare
begin
  dbms_repair.repair_freelists (
    schema_name => 'SCOTT',
    object_name => 'EMPLOYEE',
    object_type => dbms_repair.table_object);
end;
/

D.

declare
begin
  dbms_repair.rebuild_freelists (
    schema_name => 'SCOTT',
    object_name => 'EMPLOYEE',
    object_type => dbms_repair.table_object);
end;
/

D
不会

16. D. The DBMS_REPAIR package can be used to rebuild freelists on a corrupt table with the following syntax:

declare
begin
  dbms_repair.rebuild_freelists (
    schema_name => 'SCOTT',
    object_name => 'EMPLOYEE',
    object_type => dbms_repair.table_object);
end;
/

猜的没错

31.
17. Which of the following statements best describes using the DBMS_REPAIR package to resolve block corruption?
A. Resolving block corruption is a complex process, and you should be careful.
B. Resolving block corruption is a complex process, and you most often use the DBMS_REPAIR package even if the corruption is widespread.
C. Resolving block corruption is a complex process, and you should contact Oracle Support if possible.
D. Resolving block corruption is a complex process, and use of the DBMS_REPAIR package cannot introduce other problems in the database.

C

17. C. Resolving block corruption can result in the loss of data in the blocks that are corrupt. You should contact Oracle Support, if possible.

寻求技术支持

32.
18. Before attempting to resolve block corruption with the DBMS_REPAIR package, what should you consider?
A. Examine other methods of resolving the corrupt objects by rebuilding the object if the data is available.
B. Attempt to exclude the corruption by excluding the row from select statements.
C. If possible, perform an incomplete recovery.
D. All of the above.

B
不解

18. D. Before using the DBMS_REPAIR package, consider other alternatives to resolve the block corruption. Make sure you understand how else to resolve block corruption, as a backup plan if necessary.

不解
教材7-18说了一些
C. 为什么?

33.
19. Which of the following is required to perform a block media recovery with RMAN? (Choose all that apply.)
A. The datafile number and block number of the corrupted block or blocks in the UDUMP trace file
B. The tablespace number and block number of the corrupted block or blocks
C. The datafile number and block number of the corrupted block or blocks
D. The ALERT.LOG information from the ORA-01578 error

CD

19. C, D. The ORA-01578 error in the ALERT.LOG specifies the datafile number and the block number.

教材7-22

34.
20. Which of the following statements are true regarding BMR? (Choose all that apply.)
A. BMR must be performed with RMAN.
B. BMR may be performed with RMAN and SQL.
C. Incremental backups can be used to perform BMR.
D. Redo logs are not required to perform BMR if the redo log records don’t affect the corrupt block.

AD

20. A, D. BMR must be performed with RMAN only. Incremental backups cannot be used to perform BMR, because incremental backups consist of changed blocks only. All redo logs are not required to perform BMR if the damaged block does not require those redo logs.

教材7-22
见第1题

-fin-