Oracle OCP 19c 认证1Z0-083考试(100-110题) #7月最新

Posted 2022-11-29 wwwleoocom

Examine this configuration:

1.    CDB1 is a container database.

2.    PDB1 and PDB2 are pluggable databases in CDB1. 3. PDB1 and PDB2 are OPEN in READ WRITE mode. You execute these commands successfully:

Which two are true? (Choose two.)
 
A.    Uncommitted transactions in PDB1 have been rolled back.

B.    PDB1 is closed.

C.    Uncommitted transactions in CDB1 and PDB1 have been rolled back. D. CDB1 is shut down.

E. CDB1 is in MOUNT state Answer: AB
(解析:注意操作是在 pdb1 下,所以生效的范围在 pdb1.) 
62、

Which three are true about Automatic Workload Repository (AWR), Automatic Database Diagnostic Monitor (ADDM), and the Manageability Monitor (MMON) background process? (Choose three.)

A.    ADDM can recommend shrinking the buffer cache.

B.    ADDM can recommend extending the buffer cache.

C.    By default, MMON creates an AWR snapshot every 30 minutes.

D.    ADDM performs its analysis only when a DBA requests it.

E.    By default, AWR snapshots are automatically purged after eight days.

F.    AWR snapshots must be deleted when no longer required by ADDM.

Answer: ABE

(解析:ADDM 可以动态调整 sga 中各个组件的尺寸。) 
63、

Examine the command for creating pluggable database PDB2 in container database CDB2. Select three options, any one of which is required for it to execute successfully. (Choose three.)
A.    Add the FILE_NAME_CONVERT clause to the statement and set the PDB_FILE_NAME_CONVERT parameter.

B.    Add only the CREATE_FILE_DEST clause to the statement.

C.    Set only the PDB_FILE_NAME_CONVERT parameter.

D.    Set the PDB_FILE_NAME_CONVERT parameter and enable OMF.

E.    Enable only OMF.
 
F.    Add the FILE_NAME_CONVERT clause to the statement and enable Oracle Managed Files (OMF) Answer: BCE (解析:
This example assumes the following factors:

·    Storage limits are not required for the PDB. Therefore, the STORAGE clause is not required.

·    The PDB does not require a default tablespace.

·    The PATH_PREFIX clause is not required.

·    The FILE_NAME_CONVERT clause and the CREATE_FILE_DEST clause are not required.

Either Oracle Managed Files is enabled, or the PDB_FILE_NAME_CONVERT initialization parameter is set. The files associated with the seed will be copied to a new location based on the Oracle Managed Files configuration or the initialization parameter setting.

Include a CREATE_FILE_DEST clause that specifies the default file system directory or Oracle ASM disk group for the PDB's files.

Omit the CREATE_FILE_DEST clause. Use one of these techniques to specify the target locations of the files:
·    FILE_NAME_CONVERT clause

·    Enable Oracle Managed Files for the

CDB for it to determine the target locations. 
·    Specify the target locations in the PDB_FILE_NAME_CONVERT initialization parameter.

64、

Which two are true about Recovery Manager (RMAN) diagnostic message output? (Choose two.)
A.    Media Management messages for SBT devices are always written to sbtio.log.

B.    RMAN error stacks should be read from the bottom up as that is the order in which errors are generated.

C.    RMAN error stacks should be read from the top down as that is the order in which errors are generated.

D.    The RMAN LOG command line clause causes output issued during RMAN command compilation to be written to a log file and to standard output.

E.    The RMAN LOG command line clause causes output issued during RMAN command compilation to be written to a log file only.

F.    Media Management messages for SBT devices are written to an Oracle trace file.
 
Answer: BE

(解析:rman 备份到 sbt 设备时日志的位置:

Whenever channel allocation fails, the database writes a trace file to the USER_DUMP_DEST directory. The following shows sample output:

SKGFQ OSD: Error in function sbtinit on line 2278

SKGFQ OSD: Look for SBT Trace messages in file /oracle/rdbms/log/sbtio.log SBT Initialize failed for /oracle/lib/libobk.so
)

65、
Which three are true about managing memory components in an Oracle database instance?
(Choose three.)

A.    With Automatic Shared Memory Management, the database instance can increase the Large Pool size by reducing the Shared Pool size.

B.    With Automatic Memory Management, the database instance can increase the System Global Area size by reducing the Program Global Area size.

C.    Automatically tuned and resized System Global Area components will always revert to their initial sizes after an instance restart.

D.    Automatic Memory Management must be used together with locking the System Global Area into physical memory.

E.    With Automatic Shared Memory Management, the database instance can increase the Program Global Area size by reducing the System Global Area size.

F.    On Line Transaction Processing systems often use less Program Global Area than Decision Support Systems.

Answer: ABF

(解析:ASMM 和 AMM 管理的实例,都可以自动的调整 sga 组件。由于 DSS 系统处理的数 据比
较多,涉及到并行操作、排序等等,需要更多的 PGA。) 
66、

A database is configured in ARCHIVE LOG mode.

Full RMAN backups are taken and no backup to trace has been taken of the control file. A media failure has occurred.
 
In which two scenarios is complete recovery possible? (Choose two.)

A.    when any archived log from, before, or after the most recent backup is corrupt.

B.    after losing all copies of the control file

C.    after losing an archived log from after the most recent backup

D.    after losing an archived log from before the most recent backup

E.    after losing the SYSTEM tablespace Answer: DE(72 道)
(解析:要能够实现完全恢复,必须保证数据库备份之后的归档都在。)

67、
Which three are true about Database Point-in-Time Recovery? (Choose three.)

A. The database must have FLASHBACK DATABASE ON to perform Database Point-in-Time Recovery. B. The database must be in MOUNT state when performing Database Point-in-Time Recovery.

C.    Database Point-in-Time Recovery is performed by the Managed Recovery Process (MRP)

D.    The Database must be in ARCHIVE LOG mode.

E.    The target point for the recovery must be specified as a stime or System Change Number (SCN).
F.    The database must be open RESETLOGS after Database Point-in-Time Recovery.

Answer: BDF

(解析:时间点恢复必须在 mount 状态下进行;打开时必须是 resetlogs;同时必须给出一个 时间点或者 scn。这个答案中 D 答案容易让人认为是对的,其实非归档也可以做不完全恢复, 只要备份以后的日志没有发生切换,且恢复的时间点在当前的 online 日志中就可以。)

68、
Which three are true about the SQL Tuning Advisor? (Choose three.)

A.    It checks each query being analyzed for stale statistics.

B.    It checks each query being analyzed for missing statistics.

C.    It only recommends syntactic changes to SQL statements.

D.    It can recommend semantic changes to SQL statements.

E.    It considers all SQL statements being analyzed by the advisor task as a group.
 
F.    It builds SQL profiles for each poorly performing SQL statement to prevent regressions.

Answer: ABD

(解析:STA    的功能就是检查相关的统计信息,从而产生    sql    profiles。) https://docs.oracle.com/database/121/TGSQL/tgsql_sqltune.htm#TGSQL540
Use SQL Tuning Advisor to obtain recommendations for improving performance of high- load SQL statements, and prevent regressions by only executing optimal plans.

Tuning recommendations include:

·    Collection of object statistics

·    Creation of indexes

·    Rewriting SQL statements

·    Creation of SQL profiles

·    Creation of SQL plan baselines 
69、

Which two are true about duplicating pluggable databases (PDBs) with RMAN? (Choose two.)
A.    Two or more PDBs can be duplicated with the same RMAN DUPLICATE command.

B.    All tablespaces belonging to a PDB must be duplicated when duplicating the PDB.

C.    The    auxiliary    instance    is    automatically    created    with ENABLE_PLUGGABLE_DATABASE = TRUE.
D.    A user with SYSDBA or SYSBACKUP must be logged in with RMAN to the PDB to duplicate it.
E.    CDB$ROOT and PDB$SEED are automatically duplicated.

Answer: AE

(解析:在复制时可以同时复制多个 pdb,cdb$root 与 pdb$seed 会默认复制,同时需要有 答案 d
的权限登录到实例。虽然让人选择 2 个,但是有 3 个答案是对的。) 
70、

.Examine the command to duplicate a database: RMAN> DUPLICATE TARGET DATABASE TO cdb PLUGGABLE DATABASE pdb1, pdb5;
 
Which two statements are true about the DUPLICATE command?

A.    The SPFILE is copied along with the datafiles of the pluggable databases (PDBs). The root and the seed database in the container database (CDB) are also duplicated.

B.    A backup of pdb1 and pdb5 must exist before executing the command.

C.    The duplicate command first creates a backup, and then duplicates the PDBs by using the backup. D.A backup of CDB and pdb1 and pdb5 must exist before executing the command.

E.    An    auxiliary    instance    must    be    started    with    the    initialization    parameter ENABLE_PLUGGABLE_DATABASE set to TRUE.

Answer: C,E

(解析:经过 2 天的试验终于验证,克隆时没有指定 fromactivedatabase 肯定需要备份,否 则会报错。但是不知道为 什么 12.2 克隆的时候要把源数据库的备份片让目标数据库主机 能够看得见,我采取的方法是用 nfs,或者把备份片拷 贝的目标主机。

A 答案错的地方是 spfile 不会 copy 过去,而是根据辅助实例的 pfile 产生的。B 答案错是因为没有 CDB 的备份
C 答案只有在克隆时指定 from active database 才会产生备份集) ) 
71、

.RMAN is connected to the target database prod1 and an auxiliary instance in nomount state. Examine the command to create a duplicate database:

RMAN> DUPLICATE TARGET DATABASE TO dup1 FROM ACTIVE DATABASE NOFILENAMECHECK
PASSWORD FILE SPFILE;
Which two statements are true about the execution of the duplicate command?

A.    All archive redo log files are automatically copied to the duplicate database.

B.    The duplicate database has the same directory structure as the source database.

C.    The duplicate database is created by using the backups created during the execution of

D.    the duplicate command.

E.    The password file and SPFILE for the duplicate database dup1 are created in their respective default locations.

F.    The duplicate database is created without using RMAN backups and prod1 is allowed to remain
 
open during duplication.

Answer: B,F

(解析:如果复制时的目录结构与源库一样,则需要输入 NOFILENAMECHECK,由于是 ACTIVE 复制,则源数据 库可以在打开状态下进行复制。)