Basic SQL MCQs

SQL MCQ Questions

🔹 Basic SQL MCQs

1. What does SQL stand for?

   A) Structured Query List

   B) Simple Query Language

   C) Structured Query Language

   D) Standard Question Language

   Answer: C

2. Which SQL statement is used to extract data from a database?

   A) GET

   B) SELECT

   C) EXTRACT

   D) FETCH

   Answer: B

3. Which of the following is not a valid SQL data type?

   A) VARCHAR

   B) INT

   C) BOOLEAN

   D) WORD

   Answer: D

4. Which clause is used to filter records in SQL?

   A) ORDER BY

   B) WHERE

   C) GROUP BY

   D) FROM

   Answer: B

5. What does the LIMIT clause do?

   A) Limits the number of tables

   B) Limits column names

   C) Limits the number of rows returned

   D) Limits the number of users

   Answer: C

🔹 Intermediate SQL MCQs

6. Which function is used to count rows in SQL?

   A) SUM()

   B) TOTAL()

   C) COUNT()

   D) NUMBER()

   Answer: C

7. What is the purpose of the JOIN clause?

   A) To delete duplicate records

   B) To merge rows within a single table

   C) To combine rows from two or more tables

   D) To create a new table

   Answer: C

8. Which keyword is used to sort query results?

   A) FILTER BY

   B) GROUP BY

   C) SORT BY

   D) ORDER BY

   Answer: D

9. Which of the following is not a type of JOIN in SQL?

   A) INNER JOIN

   B) OUTER JOIN

   C) SIDE JOIN

   D) LEFT JOIN

   Answer: C

10. Which clause is used with GROUP BY to filter grouped data?

    A) WHERE

    B) ORDER BY

    C) HAVING

    D) LIMIT

    Answer: C

🔹 Advanced SQL MCQs

11. What does the IS NULL condition test for?

    A) Zero value

    B) Empty string

    C) Missing or undefined value

    D) All of the above

    Answer: C

12. A subquery that uses values from the outer query is called:

    A) Inline subquery

    B) Static subquery

    C) Correlated subquery

    D) Inner join

    Answer: C

13. Which statement is used to change existing data in a table?

    A) MODIFY

    B) UPDATE

    C) EDIT

    D) CHANGE

    Answer: B

14. Which SQL constraint ensures that all values in a column are different?

    A) UNIQUE

    B) CHECK

    C) NOT NULL

    D) PRIMARY

    Answer: A

15. Which of the following is not a DML (Data Manipulation Language) command?

    A) SELECT

    B) DELETE

    C) INSERT

    D) CREATE

    Answer: D