Oracle Database Multiple Choice Questions (MCQs) and Answers

Index is fragmented

Index is invalid

Statistics are outdated

Query syntax is incorrect

Poor indexing strategy

Excessive disk I/O

High contention for resources

All of the above

To define database structures

To manage database users and their privileges

To perform backups

To optimize queries

CREATE ACCOUNT username IDENTIFIED BY password;

ADD USER username WITH password;

CREATE USER username IDENTIFIED BY password;

NEW USER username WITH password;

To delete user accounts

To revoke privileges

To assign privileges to users

To modify table structures

Changes user attributes

Deletes user accounts

Assigns privileges

Modifies table structures

Roles are more granular; privileges are broad

Roles are predefined; privileges are user-defined

Roles group privileges; privileges define specific actions

Roles are for users; privileges are for tables

CREATE USER john IDENTIFIED BY password123;

CREATE ACCOUNT john PASSWORD password123;

ADD USER john WITH password123;

NEW USER john IDENTIFIED password123;

GRANT SELECT ON employees TO john;

GRANT READ ON employees TO john;

ASSIGN SELECT employees TO john;

PERMIT SELECT ON employees TO john;

REVOKE UPDATE ON employees FROM john;

REMOVE UPDATE employees FROM john;

DELETE PRIVILEGE UPDATE ON employees FROM john;

REMOVE PRIVILEGE UPDATE FROM john;

CREATE ROLE HR_MANAGER; GRANT SELECT, UPDATE ON employees TO HR_MANAGER;

CREATE ROLE HR_MANAGER WITH SELECT, UPDATE;

GRANT SELECT, UPDATE TO ROLE HR_MANAGER;

CREATE HR_MANAGER ROLE WITH PRIVILEGES;

User account is locked

User lacks privileges

Table is missing

Query syntax error

User lacks GRANT option

Table does not exist

Database is in restricted mode

Invalid syntax

Privilege not committed

Object does not exist

User was not granted access to the schema

User is locked

To optimize queries

To perform high-speed export and import operations

To create backups

To manage user privileges

EXPDP

IMPDP

EXPORT

IMPORT

Compresses data during export

Skips validation

Improves performance by bypassing the buffer

Encrypts the data

FULL exports all objects; SCHEMA exports only objects in a specific schema

FULL exports only data; SCHEMA exports data and metadata

FULL requires admin privileges; SCHEMA does not

FULL is faster than SCHEMA mode

EXPDP SYSTEM/password SCHEMAS=HR DIRECTORY=exp_dir DUMPFILE=hr_exp.dmp LOGFILE=hr_exp.log;

EXPDP HR/password FULL=y DIRECTORY=exp_dir DUMPFILE=full_exp.dmp LOGFILE=full_exp.log;

EXPORT HR/password SCHEMA_ONLY DIRECTORY=exp_dir DUMPFILE=hr_only.dmp;

EXPDP SYSTEM/password SCHEMA HR DIRECTORY=exp_dir LOG=hr_exp.log;

IMPDP SYSTEM/password DIRECTORY=exp_dir DUMPFILE=hr_exp.dmp LOGFILE=hr_imp.log;

IMPDP HR/password FILE=hr_exp.dmp LOG=hr_imp.log DIRECTORY=exp_dir;

IMPORT SYSTEM/password FILE=hr_exp.dmp LOGFILE=hr_imp.log DIRECTORY=exp_dir;

IMPDP HR/password FILE=hr_only.dmp LOGFILE=imp_hr.log DIRECTORY=exp_dir;

EXPDP SYSTEM/password TABLES=employees,departments DIRECTORY=exp_dir DUMPFILE=table_exp.dmp LOGFILE=table_exp.log;

EXPDP SYSTEM/password TABLE_ONLY=employees,departments DIRECTORY=exp_dir FILE=table_exp.dmp LOG=table_exp.log;

EXPORT SYSTEM/password TABLE=employees,departments DIRECTORY=exp_dir FILE=table_exp.dmp LOG=table_exp.log;

EXPDP SYSTEM/password TABLES=employees,departments FILE_ONLY=table_exp.dmp LOG=table_exp.log DIRECTORY=exp_dir;

Incorrect directory parameter

Insufficient privileges

Incorrect syntax

File does not exist

Dump file does not exist

Incorrect SCHEMAS parameter

Dump file corrupted

Target database is offline

To connect Oracle databases and client applications

To back up data

To monitor user sessions

To optimize queries

listener.ora

tnsnames.ora

sqlnet.ora

All of the above

Handles SQL queries

Facilitates connections to the database

Monitors database performance

Manages backups

Dedicated assigns one process per client; shared uses fewer server processes

Shared requires more memory; dedicated requires less

Dedicated is faster; shared is more secure

Both configurations are identical

lsnrctl start

lsnrctl begin

start listener

listener start

lsnrctl status

show listener status

listener status

status listener

lsnrctl reload

reload listener

listener reload

lsnrctl reconfigure