Oracle 12C--1z0-062

Posted 2021-01-16 dayu.liu

 

1.

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 to lack 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.

answer：D 指明retention为1200为不强制的。

 

2.

A user establishes a connection to a database instance by using an Oracle Net connection. You want to ensure the following:
1. The user account must be locked after five unsuccessful login attempts.
2. Data read per session must be limited for the user.
3. The user cannot have more than three simultaneous sessions.
4. 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

answer：D profile是用来对用户所能使用的数据库资源进行限制的

 

3.

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\';  --第一个hq为创建的dblink名字，第二个hq为tnsnames.ora文件里的名字
D.
CREATE DATABASE LINK HQ CONNECT TO scott IDENTIFIED BY tiger USING \'HQ\';

answer：C

 

4.

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.

answer：D 考察统计信息的窗口时间

 

 5.

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 default memory 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

answer：待确定

 

6.

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.  --逻辑上一致 （an extent is a logical unit of database storage space allocation made up of contiguous data blocks. Data blocks in an extent are logically contiguous but can be physically spread out on disk because of RAID striping and file system implementations.）
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.

answer：D

 

7.

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 block in a data file should be the same as the size of an OS block.

answer:bc

 

8.

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.

answer:AD

 

9.

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

answer：待确定

 

10.

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

answer：cd

 

11.

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.

answer：待确定

 

12.

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 HR user to the new tablespace
E. Enabling resumable space allocation by setting the RESUMABLE_TIMEOUT parameter to a nonzero value

answer：BE

Segment space management is an attribute inherited from the tablespace that contains the segment. Within a locally managed tablespace, the database can manage segments automatically or manually. For example, segments in tablespace users can be managed automatically while segments in tablespace tools are managed manually.

 

13.

Which three factors influence the optimizer\'s choice of an execution plan?
A.
the optimizer_mode initialization parameter
B.
operating system (OS) statistics
C.
cardinality estimates
D.
object statistics in the data dictionary
E.
fixed baselines

待确定：ACD

 

14.

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.

待确定：

 

 15.

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.
The Database 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.

待确定：D