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- December 5, 2024
Question 21
Which SQL statement creates a sequence in Oracle?
A) CREATE SEQUENCE sequence_name;
B) CREATE NEXTVAL sequence_name;
C) CREATE NEW SEQUENCE sequence_name;
D) CREATE ORDERED sequence_name;
Correct Answer: A) CREATE SEQUENCE sequence_name;
Explanation: The correct SQL statement to create a sequence is CREATE SEQUENCE sequence_name.
Question 22
Which Oracle background process ensures that data blocks in the buffer cache are written to disk?
A) SMON
B) DBWn
C) CKPT
D) PMON
Correct Answer: B) DBWn
Explanation: The DBWn (Database Writer) process ensures that dirty data blocks in the buffer cache are written to disk.
Question 23
Which of the following is used to control the automatic extension of a data file in Oracle?
A) MAXSIZE
B) AUTOEXTEND
C) RESIZE
D) NEXT
Correct Answer: B) AUTOEXTEND
Explanation: AUTOEXTEND allows a data file to grow automatically as needed, according to the configured parameters.
Question 24
Which Oracle tool is used to generate and analyze AWR reports?
A) SQL*Loader
B) RMAN
C) Enterprise Manager
D) Oracle Net Manager
Correct Answer: C) Enterprise Manager
Explanation: Oracle Enterprise Manager can be used to generate and analyze Automatic Workload Repository (AWR) reports for performance tuning.
Question 25
What is the purpose of Oracle’s SQL*Loader utility?
A) To load data from external files into Oracle tables
B) To execute SQL scripts automatically
C) To monitor database performance
D) To generate reports on database activity
Correct Answer: A) To load data from external files into Oracle tables
Explanation: SQL*Loader is a utility used to load data from external files into Oracle tables.
Question 26
Which SQL statement is used to alter the size of a data file in Oracle?
A) RESIZE FILE filename;
B) ALTER DATABASE DATAFILE filename RESIZE;
C) ALTER DATAFILE filename CHANGE SIZE;
D) MODIFY DATAFILE filename SIZE;
Correct Answer: B) ALTER DATABASE DATAFILE filename RESIZE;
Explanation: The correct SQL statement to alter the size of a data file is ALTER DATABASE DATAFILE filename RESIZE.
Question 27
Which of the following is a valid index type in Oracle?
A) Primary Index
B) Function-based Index
C) Unique Index
D) Secondary Index
Correct Answer: B) Function-based Index
Explanation: A function-based index in Oracle indexes the result of a function applied to a column, enhancing query performance.
Question 28
What is Oracle’s Real Application Clusters (RAC) used for?
A) Data warehousing
B) High availability and scalability
C) Data replication between databases
D) Memory management
Correct Answer: B) High availability and scalability
Explanation: Oracle RAC enables multiple instances to access a single database, providing high availability and scalability.
Question 29
Which of the following is a dynamic performance view in Oracle?
A) DBA_USERS
B) V$SESSION
C) ALL_TABLES
D) DBA_DATA_FILES
Correct Answer: B) V$SESSION
Explanation: V$SESSION is a dynamic performance view that provides information about current database sessions.
Question 30
What does the Oracle listener process do?
A) Monitors user sessions and terminates idle ones
B) Manages memory allocation for user sessions
C) Listens for incoming database connection requests
D) Writes the redo log buffer to disk
Correct Answer: C) Listens for incoming database connection requests
Explanation: The Oracle listener process is responsible for handling incoming requests from clients trying to connect to the database.
Question 31
Which of the following components is part of Oracle’s System Global Area (SGA)?
A) PGA
B) Data Dictionary Cache
C) Background Processes
D) Redo Log Files
Correct Answer: B) Data Dictionary Cache
Explanation: The Data Dictionary Cache is a component of the SGA that stores information about the database's structure and schema.
Question 32
Which SQL statement disables a constraint in Oracle?
A) ALTER TABLE table_name REMOVE CONSTRAINT constraint_name;
B) ALTER TABLE table_name DROP CONSTRAINT constraint_name;
C) ALTER TABLE table_name DISABLE CONSTRAINT constraint_name;
D) ALTER TABLE table_name CANCEL CONSTRAINT constraint_name;
Correct Answer: C) ALTER TABLE table_name DISABLE CONSTRAINT constraint_name;
Explanation: The correct SQL statement to disable a constraint is ALTER TABLE DISABLE CONSTRAINT.
Question 33
What is the primary function of Oracle’s LogMiner utility?
A) To generate data recovery reports
B) To analyze redo logs for changes to the database
C) To monitor user sessions
D) To manage data dictionary views
Correct Answer: B) To analyze redo logs for changes to the database
Explanation: LogMiner is used to analyze changes in the redo logs, allowing users to track specific modifications made to the database.
Question 34
Which SQL statement is used to change the default tablespace of a user?
A) ALTER USER username SET DEFAULT TABLESPACE tablespace_name;
B) ALTER TABLESPACE tablespace_name SET DEFAULT;
C) ALTER USER username SET TABLESPACE tablespace_name;
D) ALTER USER username DEFAULT TABLESPACE tablespace_name;
Correct Answer: D) ALTER USER username DEFAULT TABLESPACE tablespace_name;
Explanation: The correct SQL statement to change a user's default tablespace is ALTER USER DEFAULT TABLESPACE.
Question 35
Which Oracle utility is used to create logical backups of tables?
A) RMAN
B) SQL*Loader
C) Data Pump
D) Export/Import
Correct Answer: C) Data Pump
Explanation: Oracle Data Pump is used to create logical backups by exporting tables, schemas, or entire databases.
Question 36
Which Oracle background process is responsible for checkpointing?
A) DBWn
B) CKPT
C) SMON
D) LGWR
Correct Answer: B) CKPT
Explanation: The CKPT (Checkpoint) background process is responsible for signaling when a checkpoint occurs, ensuring that all data files and control files are synchronized.
Question 37
What is Oracle’s Materialized View used for?
A) To provide a logical backup of the table
B) To store the result of a query for faster retrieval
C) To manage user sessions
D) To analyze redo logs for changes
Correct Answer: B) To store the result of a query for faster retrieval
Explanation: A Materialized View stores the result of a query and can be refreshed periodically, providing faster query performance.
Question 38
Which of the following is true about Oracle’s redo log files?
A) They are written to disk only during checkpoints.
B) They are used to recover changes made to the database after a failure.
C) They store a backup of the data files.
D) They store a copy of archived data.
Correct Answer: B) They are used to recover changes made to the database after a failure.
Explanation: Redo log files are used to store all changes made to the database and are critical for recovering the database after a failure.
Question 39
Which of the following options allows a table to automatically generate sequential numbers in Oracle?
A) AUTO_INCREMENT
B) DEFAULT NEXT VALUE
C) CREATE SEQUENCE
D) NEXTVAL
Correct Answer: C) CREATE SEQUENCE
Explanation: The CREATE SEQUENCE statement allows a table to generate sequential numbers for columns, typically for use as primary keys.
Question 40
What is the purpose of Oracle’s SCN (System Change Number)?
A) It represents the timestamp of a specific change made in the database.
B) It stores the sequence number of the last transaction.
C) It is a unique identifier for each transaction in the redo logs.
D) It provides a unique identifier for recovery operations.
Correct Answer: A) It represents the timestamp of a specific change made in the database.
Explanation: The System Change Number (SCN) is a unique identifier assigned to each transaction, representing the point in time when changes were made.
