Comparison operators in MySQL - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to select all rows where age is equal to 30.

MySQL

SELECT * FROM users WHERE age [1] 30;

Drag options to blanks, or click blank then click option'

A>

B!=

C=

D<

Attempts:

3 left

💡 Hint

Common Mistakes

Using '!=' instead of '=' will select rows where age is not 30.

Using '>' or '<' will select rows with age greater or less than 30, not equal.

The equal sign = is used to compare if two values are the same.

2fill in blank

medium

Complete the code to select all rows where salary is greater than 50000.

MySQL

SELECT * FROM employees WHERE salary [1] 50000;

Drag options to blanks, or click blank then click option'

A>

B<=

C=

D<

Attempts:

3 left

💡 Hint

Common Mistakes

Using '<' or '<=' will select salaries less than or equal to 50000.

Using '=' will select only salaries exactly 50000.

The greater than operator > selects values larger than the given number.

3fill in blank

hard

Fix the error in the code to select rows where score is not equal to 100.

MySQL

SELECT * FROM results WHERE score [1] 100;

Drag options to blanks, or click blank then click option'

A<>

B!=

C==

D=

Attempts:

3 left

💡 Hint

Common Mistakes

Using == causes syntax errors in SQL.

Using = selects rows equal to 100, not different.

In MySQL, the not equal operator can be written as <> or !=. Both are valid, but <> is often preferred for compatibility.

4fill in blank

hard

Fill both blanks to select rows where price is between 10 and 20 (inclusive).

MySQL

SELECT * FROM products WHERE price [1] 10 AND price [2] 20;

Drag options to blanks, or click blank then click option'

A>=

B<

C<=

D>

Attempts:

3 left

💡 Hint

Common Mistakes

Using > or < excludes the boundary values.

Mixing up the operators will select wrong price ranges.

To select prices between 10 and 20 including both, use >= for the lower bound and <= for the upper bound.

5fill in blank

hard

Fill all three blanks to select rows where quantity is greater than 5, less than 15, and not equal to 10.

MySQL

SELECT * FROM inventory WHERE quantity [1] 5 AND quantity [2] 15 AND quantity [3] 10;

Drag options to blanks, or click blank then click option'

A>

B<

C!=

D=

Attempts:

3 left

💡 Hint

Common Mistakes

Using = instead of != will select quantity equal to 10.

Using wrong comparison operators will select incorrect rows.

This query selects quantities greater than 5, less than 15, and not equal to 10 using >, <, and != operators respectively.