单选题
Choose the best answer Examine these statements and results:
SQL> SELECT COUNT() FROM emp;
COUNT ()

14
SQL> CREATE GLOBAL TEMPORARY TABLE t_emp AS SELECT * FROM
emp;
Table created.
SQL> INSERT INTO t_emp SELECT * FROM emp;
14 rows created.
SQL> COMMIT;
Commit complete.
SQL> INSERT INTO t_emp SELECT * FROM emp;
14 rows created.
SQL> SELECT COUNT(*) FROM t_emp;
How many rows are retrieved by the last query?

A、

B、

C、

D、

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单选题 choose one Which statement is true about profiles?

A、

A profile can be assigned only to one user.

B、

A user can exist without any profile.

C、

Password management using profiles is always enabled.

D、

Resource limits specified in a profile assigned to a user are always enabled.

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单选题 The SCOTT/TIGER user exists in two databases,

BOSTON_DB and DALLAS_DB, in two different locations.

Each database has a tnsnames.ora file defining DALLAS_DB as a service name.

Examine this command:

CREATE DATABASE LINK dblink1 CONNECT TO scott IDENTIFIED BY tiger USING ‘dallas_db’;

How do you execute the command so that only SCOTT in BOSTON_DB can access the SCOTT schema in DALLAS_DB?

A、

as SCOTT in DALLAS_DB

B、

as SCOTT in both the databases

C、

as SYS in both the databases

D、

as SCOTT in BOSTON_DB

E、

as SCOTT in BOSTON_DB and SYS in DALLAS_DB

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单选题 Choose the best answer. Which statement is true about database links?

A、

A public database link can be used by a user connected to the local database instance to connect to any schema in the remote database instance.

B、

Private database link creation requires the same user to exist in both the local and the remote databases.

C、

A database link created in a database allows a connection from that database's instance to the target database's instance, but not vice versa.

D、

A public database link can be created only by sys.

E、

A database link can be created only between two Oracle databases.

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单选题 Choose the best answer. Your database instance is started with an SPFILE.

A PFILE is also available.

You execute this command:

ALTER SYSTEM SET DB_CACHE_SIZE=100K;

Where is the value changed?

A、

in the SPFILE, PFILE, and memory

B、

only in memory

C、

in the SPFILE and in memory

D、

only in the SPFILE

E、

in the SPFILE and PFILE

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单选题 You want to use table compression suitable for OLTP that will:

1. Compress rows for all DML statements on that table

2. Minimize the overheads associated with compression

Which compression option is best suited for this?

A、

COLUMN STORE COMPRESS FOR QUERY LOW

B、

ROW STORE COMPRESS BASIC

C、

COLUMN STORE COMPRESS FOR ARCHIVE LOW

D、

ROW STORE COMPRESS ADVANCED

E、

COLUMN STORE COMPRESS FOR ARCHIVE HIGH

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单选题 In the spfile of a single instance database, LOCAL_LISTENER is set to LISTENER_1. The TNSNAMES.ORA file in $ORACLE_HOME/network/admin in the database home contains:

Which statement is true?

A、

LISTENER_1 must also be defined in the LISTENER.ORA file to enable dynamic service registration

B、

The definition for LISTENER_1 requires a CONNECT_DATA section to enable dynamic service Registration

C、

Dynamic service registration cannot be used for this database instance

D、

There are two listeners named LISTENER and LISTENER_1 running simultaneously using port 1521 on the same host as the database instances

E、

The LREG process registers services dynamically with the LISTENER_1 listener

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单选题 Your database instance is started with a PFILE. Examine these parameters:

You want to increase the size of the buffer cache. Free memory is available to increase the size of the buffer cache.

You execute the command:

SQL> ALTER SYSTEM SET DB_CACHE_SIZE=1024M;

What is the outcome?

A、

The value is changed only in the PFILE and takes effect at the next instance startup

B、

The value is changed for the current instance and in the PFILE

C、

It fails because the SCOPE clause is missing

D、

Change is applied to the current instance, but does not persist after instance restart

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单选题 Choose the best answer. Examine these commands:

CONNECT / AS SYSDBA

CREATE DIRECTORY dumpdir AS ‘/u01/app’;

Directory created.

GRANT READ,WRITE ON DIRECTORY dumpdir TO PUBLIC;

Grant succeeded.

Create USER TEST IDENTIFIED BY test;

User created.

GRANT CREATE SESSION,RESOURCE,UNLIMITED TABLESPACE TO test;

Grant succeeded.

CONN test/test.

Connected.

CREATE TABLE test_employees (id NUMBER(3), name VARCHAR2(20), salary NUMBER (7));

Table created.

SQL> CREATE SYNONYM emp FOR test_employees;

Synonym create.

Now examine this command: $ expdp test/test DIRECTORY=dumpdir DUMPFILE=test_emp.dmp LOGFILE=test.log TABLES=emp

Which is true?

A、

It throws an error as Data Pump cannot find a table called TEST.EMP.

B、

It throws an error as the QUERY parameter is not supported on an empty table.

C、

It performs the export successfully.

D、

It throws an error as the table test_employees is empty and CONTENT=data_only is specified.

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