SQL Quizzes: Test Your Database Management Skills

Question 1

Which SQL statement creates a table called 'Students' with columns 'ID', 'Name', and 'Grade'?

Accepted Answer

CREATE TABLE Students (ID INT, Name TEXT, Grade REAL);

Answer

CREATE TABLE 'Students' (ID INT, Name VARCHAR(255), Grade NUMERIC);

Answer

CREATE TABLE Students (Name VARCHAR(255), Grade NUMERIC, ID INT);

Question 2

For creating a new table in SQL, which statement do you employ?

Accepted Answer

CREATE TABLE

Answer

ADD TABLE

Answer

MAKE TABLE

Answer

INSERT TABLE

Question 3

In a database table, what is the main purpose of a primary key?

Accepted Answer

Ensuring unique identification for each row in the table

Answer

Storing the most crucial data in the table

Answer

Establishing relationships between tables

Answer

Enforcing data consistency

Question 4

Which SQL operator do you use to combine results from multiple queries?

Accepted Answer

UNION

Answer

AND

Answer

OR

Answer

JOIN

Question 5

For storing a customer's phone number, which data type would be most suitable?

Accepted Answer

VARCHAR

Answer

INT

Answer

DATE

Answer

BOOLEAN

Question 6

Which SQL function do you utilize to determine the maximum value within a column?

Accepted Answer

MAX()

Answer

MIN()

Answer

AVG()

Answer

SUM()

Question 7

Which SQL command do you use to modify data in a table?

Accepted Answer

UPDATE

Answer

MODIFY

Answer

EDIT

Answer

CHANGE

Question 8

Define a subquery. Explain its purpose and how it is used.

Accepted Answer

A query embedded within another query

Answer

A table linked to another table

Answer

A function returning a set of rows

Answer

A constraint applied to a column

Question 9

Which SQL statement is used to add a new record to a table?

Accepted Answer

INSERT INTO table_name (column1, column2, ...) VALUES (value1, value2, ...)

Answer

SELECT * FROM table_name

Answer

UPDATE table_name SET column_name = value WHERE condition

Answer

DELETE FROM table_name WHERE condition

Question 10

Which of these is NOT a standard SQL data type?

Accepted Answer

CURRENCY

Answer

INTEGER

Answer

BOOLEAN

Answer

TEXT

Question 11

How does the GROUP BY clause contribute to effective data analysis in SQL?

Accepted Answer

Groups and aggregates data based on specified columns

Answer

Filters data based on specified criteria

Answer

Sorts data in ascending or descending order

Answer

Inserts new rows into a table

Question 12

Which SQL syntax is correct for creating a new table called 'customers' with columns 'id' (integer), 'name' (text), and 'email' (text)?

Accepted Answer

CREATE TABLE customers (id INT, name TEXT, email TEXT)

Answer

CREATE TABLE customers (name TEXT, id INT, email TEXT)

Answer

CREATE TABLE customers (id TEXT, name INT, email TEXT)

Answer

CREATE customers (id INT, name TEXT, email TEXT)

Question 13

Which SQL statement retrieves all data from the 'customers' table?

Accepted Answer

SELECT * FROM customers

Answer

SELECT entire FROM customers

Answer

GET customers

Answer

FETCH all FROM customers

Question 14

Which SQL clause is used to specify conditions for filtering rows?

Accepted Answer

WHERE

Answer

IF

Answer

FILTER

Answer

SELECT

Question 15

Which SQL statement updates the 'email' field for the customer with 'id' equal to 1?

Accepted Answer

UPDATE customers SET email = 'updated@example.com' WHERE id = 1

Answer

UPDATE customers (email) SET 'updated@example.com' WHERE id = 1

Answer

UPDATE customers email SET updated@example.com WHERE id = 1

Answer

UPDATE customers email = 'updated@example.com' WHERE id = 1

Question 16

Which SQL clause groups data based on a specified column?

Accepted Answer

GROUP BY

Answer

ORDER BY

Answer

SORT BY

Answer

CLASSIFY BY

Question 17

Which SQL statement is used to select specific columns of data from a table?

Accepted Answer

SELECT

Answer

INSERT

Answer

UPDATE

Answer

DELETE

Question 18

What is the primary purpose of a WHERE clause in an SQL statement?

Accepted Answer

To filter data based on specified conditions

Answer

To add new data to a table

Answer

To modify existing data in a table

Answer

To delete data from a table

Question 19

Which data type should be used to store whole numbers in an SQL database?

Accepted Answer

INTEGER

Answer

VARCHAR

Answer

FLOAT

Answer

BOOLEAN

Question 20

What is the primary distinction between a primary key and a foreign key in the context of an SQL database?

Accepted Answer

A primary key uniquely identifies each row in a table, while a foreign key references a primary key in another table

Answer

A foreign key uniquely identifies each row in a table, while a primary key references a foreign key in another table

Answer

Both primary and foreign keys can be used to uniquely identify rows in a table

Answer

Neither primary nor foreign keys are used for identifying rows in a table

Question 21

Which SQL statement is primarily used for creating a new table?

Accepted Answer

CREATE TABLE

Answer

INSERT INTO

Answer

SELECT FROM

Answer

UPDATE SET

Question 22

What is the main purpose of using an ORDER BY clause in an SQL statement?

Accepted Answer

To sort the results of a query in ascending or descending order

Answer

To group the results of a query by specified columns

Answer

To filter the results of a query based on specified conditions

Answer

To add new data to a table

Question 23

What is the primary purpose of using a JOIN in an SQL statement?

Accepted Answer

To combine rows from two or more tables based on a common column

Answer

To sort the results of a query in ascending or descending order

Answer

To filter the results of a query based on specified conditions

Answer

To add new data to a table

Question 24

Which SQL statement is used to modify existing data in a table?

Accepted Answer

UPDATE

Answer

INSERT

Answer

SELECT

Answer

DELETE

Question 25

What is the main difference between an index and a constraint in the context of an SQL database?

Accepted Answer

An index speeds up data retrieval, while a constraint enforces data integrity

Answer

A constraint speeds up data retrieval, while an index enforces data integrity

Answer

Both indexes and constraints can be used to speed up data retrieval

Answer

Neither indexes nor constraints are used to improve data access or integrity

Question 26

In SQL, how do you create a new database?

Accepted Answer

CREATE DATABASE

Answer

USE DATABASE

Answer

DROP DATABASE

Answer

ALTER DATABASE

Question 27

Which SQL statement is used to retrieve data from a table?

Accepted Answer

SELECT

Answer

INSERT INTO

Answer

UPDATE

Answer

DELETE

Question 28

In SQL, which data type is appropriate for storing whole numbers?

Accepted Answer

INTEGER

Answer

VARCHAR

Answer

FLOAT

Answer

BOOLEAN

Question 29

What is the key distinction between a primary key and a foreign key in SQL?

Accepted Answer

A primary key uniquely identifies each row in a table, whereas a foreign key references a primary key in another table.

Answer

A foreign key uniquely identifies each row in a table, whereas a primary key references another table's foreign key.

Answer

Both primary and foreign keys serve as unique identifiers for each row in a table.

Answer

There is no difference between primary and foreign keys.

Question 30

Which SQL operator is used for value comparison?

Accepted Answer

=

Answer

>

Answer

AND

Answer

NOT

Question 31

What is the primary function of a SQL JOIN?

Accepted Answer

To merge rows from multiple tables based on a common column

Answer

To create a completely new table

Answer

To remove rows from a table

Answer

To modify rows in a table

Question 32

In SQL, which function can be used to find the maximum value in a column?

Accepted Answer

MAX()

Answer

MIN()

Answer

AVG()

Answer

COUNT()

Question 33

What is the primary purpose of an ORDER BY clause in SQL?

Accepted Answer

To sort query results in ascending or descending order

Answer

To filter query results based on specific criteria

Answer

To group query results by a specific column

Answer

To limit the number of rows returned in a query

Question 34

In SQL, which statement is used to delete a table?

Accepted Answer

DROP TABLE

Answer

DELETE TABLE

Answer

TRUNCATE TABLE

Answer

ALTER TABLE

Question 35

What is the purpose of a WHERE clause in SQL?

Accepted Answer

To filter query results based on specific criteria

Answer

To sort query results in ascending or descending order

Answer

To group query results by a specific column

Answer

To limit the number of rows returned in a query

Question 36

What is the primary function of the WHERE clause in an SQL SELECT statement?

Accepted Answer

Filters rows based on specified conditions

Answer

Sorts rows in the result set

Answer

Groups rows in the result set

Answer

Deletes rows from the table

Question 37

In SQL, which clause allows you to obtain only unique rows from a table?

Accepted Answer

DISTINCT

Answer

WHERE

Answer

GROUP BY

Answer

HAVING

Question 38

The purpose of the 'INNER JOIN' keyword is to:

Accepted Answer

Combine rows from two tables based on a common column

Answer

Extract rows from one table based on criteria in another

Answer

Create a new table by merging multiple tables

Answer

Delete rows from one table based on values in another

Question 39

Which data type in SQL is specifically designed to store date and time information?

Accepted Answer

DATETIME

Answer

INT

Answer

FLOAT

Answer

STRING

Question 40

Distinguish between a primary key and a foreign key. Which one:

Accepted Answer

Identifies a unique row in a table, while the other references a row in another

Answer

Identifies a unique row in a table, while the other is referenced by a row in another

Answer

Both uniquely identify rows in tables

Answer

They are essentially the same thing

Question 41

Among the following, identify the operator that is NOT valid in SQL:

Accepted Answer

&&

Answer

<

Answer

>

Answer

=

Question 42

What is the primary function of the 'ORDER BY' clause?

Accepted Answer

Arrange the results of a query in a specific order

Answer

Filter rows based on specified conditions

Answer

Group rows based on common values

Answer

Limit the number of rows retrieved

Question 43

Which of these is a well-known example of a database management system (DBMS)?

Accepted Answer

MySQL

Answer

Microsoft Office

Answer

Google Docs

Answer

Adobe Photoshop

Question 44

What is the primary purpose of a 'WHERE' clause in SQL?

Accepted Answer

Establish conditions for row selection

Answer

Generate a new table based on filtered data

Answer

Remove rows from a table

Answer

Modify data in a table

Question 45

Which of the following is NOT among the typical responsibilities of a database administrator (DBA)?

Accepted Answer

Executing SQL queries

Answer

Managing database performance

Answer

Creating user accounts

Answer

Implementing security measures for the database

Question 46

The 'GROUP BY' clause in SQL primarily serves to:

Accepted Answer

Combine rows based on shared values

Answer

Filter rows based on specific conditions

Answer

Arrange the results of a query in a specific order

Answer

Restrict the number of rows retrieved

Question 47

Which SQL command is used to create a database with the specified name?

Accepted Answer

CREATE DATABASE [Database_Name]

Answer

CREATE TABLES [Database_Name]

Answer

MAKE DATABASE [Database_Name]

Answer

ADD DATABASE [Database_Name]

Question 48

Which SQL function is used to calculate the maximum value within a set of data?

Accepted Answer

MAX(column_name)

Answer

COUNT(column_name)

Answer

SUM(column_name)

Answer

MIN(column_name)

Question 49

Which SQL statement is used to permanently remove data from a table?

Accepted Answer

DELETE FROM [table_name] [condition]

Answer

DROP [table_name]

Answer

REMOVE FROM [table_name] [condition]

Answer

ERASE FROM [table_name] [condition]

Question 50

Which SQL keyword is used to define a column as the primary key of a table?

Accepted Answer

PRIMARY KEY

Answer

FOREIGN KEY

Answer

NOT NULL

Answer

UNIQUE

Question 51

Which SQL statement is used to modify data within a table?

Accepted Answer

UPDATE [table_name] SET [column_name] = [new_value] [condition]

Answer

MODIFY [table_name] SET [column_name] = [new_value] [condition]

Answer

CHANGE [table_name] SET [column_name] = [new_value] [condition]

Answer

EDIT [table_name] SET [column_name] = [new_value] [condition]

Question 52

Which SQL join type returns all rows from both tables, even if there are no matching values?

Accepted Answer

FULL OUTER JOIN

Answer

INNER JOIN

Answer

LEFT OUTER JOIN

Question 53

Which SQL index type is used to improve query performance by creating a sorted copy of a table column?

Accepted Answer

B-tree index

Answer

Bitmap index

Answer

Full-text index

Answer

Hash index