SQL Revision MCQs | 25 Practice Questions with Answers | CBSE Class 12 Informatics Practices (IP)
Class 12 · Informatics Practices
SQL Revision MCQs (25 Questions)
Practice these multiple-choice questions to revise the SQL concepts covered in Class XI. Click Show Answer to reveal the correct answer and explanation.
Q1. What does DBMS stand for?
A. Data Backup Management System
B. Database Management System
C. Data Binary Management System
D. Database Memory System
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Answer: B. Database Management System
Explanation: A DBMS is software used to create, store, retrieve, and manage databases efficiently.
Q2. Which of the following is an example of an RDBMS?
A. MySQL
B. Microsoft Excel
C. Notepad
D. Paint
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Answer: A. MySQL
Explanation: MySQL is a Relational Database Management System (RDBMS).
Q3. A database is a:
A. Collection of related data
B. Collection of programs
C. Collection of images only
D. Collection of operating systems
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Answer: A.
Explanation: A database is an organized collection of related data.
Q4. In a database table, a row is also known as a:
A. Field
B. Attribute
C. Record
D. Column
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Answer: C. Record
Explanation: Each row in a table represents one complete record.
Q5. In a database table, a column is also known as a:
A. Record
B. Attribute (Field)
C. Tuple
D. Row
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Answer: B.
Explanation: A column represents an attribute or field of the table.
Q6. Which key uniquely identifies each record in a table?
A. Foreign Key
B. Candidate Key
C. Primary Key
D. Alternate Key
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Answer: C. Primary Key
Explanation: A Primary Key uniquely identifies every record in a table.
Q7. SQL stands for:
A. Structured Query Language
B. Simple Query Language
C. System Query Language
D. Standard Question Language
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Answer: A.
Explanation: SQL is the standard language used to communicate with relational databases.
Q8. Which SQL command is used to create a table?
A. INSERT
B. CREATE TABLE
C. SELECT
D. UPDATE
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Answer: B.
Explanation: The CREATE TABLE command creates a new table in a database.
Q9. Which SQL command is used to add records to a table?
A. UPDATE
B. INSERT
C. DELETE
D. ALTER
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Answer: B.
Explanation: The INSERT command adds new records to a table.
Q10. Which SQL command retrieves data from a table?
A. FETCH
B. SELECT
C. SHOW
D. VIEW
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Answer: B.
Explanation: The SELECT statement is used to retrieve data from one or more tables.
Q11. Which SQL command modifies existing records?
A. INSERT
B. UPDATE
C. DELETE
D. CREATE
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Answer: B.
Explanation: The UPDATE command modifies existing records in a table.
Q12. Which SQL command removes records from a table?
A. DROP
B. DELETE
C. REMOVE
D. ERASE
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Answer: B.
Explanation: The DELETE command removes records from a table without deleting the table structure.
Q13. Which clause is used to filter records in SQL?
A. ORDER BY
B. GROUP BY
C. WHERE
D. HAVING
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Answer: C.
Explanation: The WHERE clause filters records based on specified conditions.
Q14. Which keyword removes duplicate values from the result?
A. UNIQUE
B. DISTINCT
C. DIFFERENT
D. FILTER
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Answer: B.
Explanation: The DISTINCT keyword returns only unique values.
Q15. Which clause arranges records in ascending or descending order?
A. GROUP BY
B. WHERE
C. ORDER BY
D. HAVING
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Answer: C.
Explanation: The ORDER BY clause sorts query results in ascending (ASC) or descending (DESC) order.
Q16. Which category of SQL commands is used to create and modify the structure of database objects?
A. DML (Data Manipulation Language)
B. DDL (Data Definition Language)
C. DCL (Data Control Language)
D. TCL (Transaction Control Language)
Show Answer
Answer: B. DDL (Data Definition Language)
Explanation: DDL commands such as CREATE, ALTER, and DROP are used to define or modify database structures.
Q17. Which category of SQL commands is used to insert, update, delete, and retrieve data?
A. DDL
B. DML
C. DCL
D. TCL
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Answer: B. DML
Explanation: DML commands include INSERT, UPDATE, DELETE, and SELECT.
Q18. Which SQL command is used to change the structure of an existing table?
A. MODIFY
B. ALTER TABLE
C. UPDATE TABLE
D. CHANGE TABLE
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Answer: B. ALTER TABLE
Explanation: ALTER TABLE is used to add, modify, or delete columns from an existing table.
Q19. Which SQL command permanently removes an entire table along with its data?
A. DELETE
B. REMOVE
C. DROP TABLE
D. ERASE
Show Answer
Answer: C. DROP TABLE
Explanation: DROP TABLE deletes both the table structure and all the records stored in it.
Q20. Which SQL statement will display only those students whose marks are greater than 80?
A. SELECT * FROM Student WHERE Marks > 80;
B. SELECT Student Marks > 80;
C. SHOW Student WHERE Marks > 80;
D. DISPLAY Student;
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Answer: A.
Explanation: The WHERE clause filters records according to the specified condition.
Q21. A school database contains duplicate city names. Which keyword should be used to display each city only once?
A. UNIQUE
B. DISTINCT
C. DIFFERENT
D. FILTER
Show Answer
Answer: B. DISTINCT
Explanation: The DISTINCT keyword removes duplicate values from the result set.
Q22. Which SQL clause is used to arrange employee salaries from highest to lowest?
A. ORDER BY Salary DESC
B. ORDER BY Salary ASC
C. GROUP BY Salary
D. SORT Salary
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Answer: A.
Explanation: The DESC keyword sorts data in descending order.
Q23. Which SQL statement correctly displays all records from the Employee table?
A. SELECT * FROM Employee;
B. SHOW Employee;
C. DISPLAY Employee;
D. GET Employee;
Show Answer
Answer: A.
Explanation: SELECT * retrieves all columns and all records from a table.
Q24. Which of the following statements is TRUE?
A. CREATE TABLE creates a new table.
B. INSERT adds records to a table.
C. UPDATE modifies existing records.
D. All of these.
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Answer: D. All of these.
Explanation: These are the standard purposes of the SQL commands CREATE TABLE, INSERT, and UPDATE.
Q25. Which statement best summarizes SQL?
A. SQL is the standard language for relational databases.
B. SQL is used to create, retrieve, update, and delete data.
C. SQL includes DDL and DML commands for managing databases.
D. All of these.
Show Answer
Answer: D. All of these.
Explanation: SQL provides a complete set of commands for defining database structures and manipulating data in relational databases.
Answer Key
| Q.No. | Answer | Q.No. | Answer | Q.No. | Answer |
|---|---|---|---|---|---|
| 1 | B | 11 | B | 21 | B |
| 2 | A | 12 | B | 22 | A |
| 3 | A | 13 | C | 23 | A |
| 4 | C | 14 | B | 24 | D |
| 5 | B | 15 | C | 25 | D |
| 6 | C | 16 | B | ||
| 7 | A | 17 | B | ||
| 8 | B | 18 | B | ||
| 9 | B | 19 | C | ||
| 10 | B | 20 | A |
Practice Tips
- Revise the basic database concepts:
- Database → Collection of related data.
- DBMS → Software used to manage databases.
- RDBMS → Stores data in related tables (e.g., MySQL).
- Remember important SQL command categories:
- DDL →
CREATE,ALTER,DROP - DML →
SELECT,INSERT,UPDATE,DELETE
- DDL →
- Know the purpose of common SQL commands:
CREATE TABLE→ Creates a table.INSERT→ Adds new records.SELECT→ Retrieves data.UPDATE→ Modifies existing records.DELETE→ Removes records.DROP TABLE→ Deletes the table permanently.
- Understand important clauses:
WHERE→ Filters records.DISTINCT→ Displays unique values.ORDER BY ASC→ Sorts in ascending order.ORDER BY DESC→ Sorts in descending order.
- Primary Key: Every table should have a Primary Key to uniquely identify each record.
- CBSE Tip: Competency-based questions often present a real-life scenario and ask you to identify the correct SQL command or clause. Focus on understanding the purpose of each command rather than memorizing syntax alone.