HAVING for filtering groups in PostgreSQL - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to filter groups having more than 3 orders.

PostgreSQL

SELECT customer_id, COUNT(*) FROM orders GROUP BY customer_id HAVING COUNT(*) [1] 3;

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

A>

B<

C=

D<=

Attempts:

3 left

💡 Hint

Common Mistakes

Using WHERE instead of HAVING for aggregated conditions.

Using '<' instead of '>' causing wrong filtering.

The HAVING clause filters groups where the count of orders is greater than 3.

2fill in blank

medium

Complete the code to select product categories with total sales equal to 1000.

PostgreSQL

SELECT category, SUM(sales) FROM products GROUP BY category HAVING SUM(sales) [1] 1000;

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

A<

B=

C>

D!=

Attempts:

3 left

💡 Hint

Common Mistakes

Using WHERE instead of HAVING for aggregate conditions.

Using '>' or '<' when exact match is needed.

The HAVING clause filters groups where the total sales exactly equal 1000.

3fill in blank

hard

Fix the error in the code to filter groups with average rating at least 4.

PostgreSQL

SELECT product_id, AVG(rating) FROM reviews GROUP BY product_id HAVING AVG(rating) [1] 4;

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

A<

B=

C>=

D<=

Attempts:

3 left

💡 Hint

Common Mistakes

Using '>' excludes ratings exactly 4.

Using WHERE instead of HAVING for aggregate filtering.

The HAVING clause filters groups where the average rating is greater than or equal to 4.

4fill in blank

hard

Fill both blanks to select departments with more than 5 employees and total salary less than 50000.

PostgreSQL

SELECT department, COUNT(*) AS emp_count, SUM(salary) AS total_salary FROM employees GROUP BY department HAVING COUNT(*) [1] 5 AND SUM(salary) [2] 50000;

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

A>

B<

C>=

D<=

Attempts:

3 left

💡 Hint

Common Mistakes

Using WHERE instead of HAVING for aggregate conditions.

Mixing up comparison operators causing wrong filtering.

The HAVING clause filters departments with employee count greater than 5 and total salary less than 50000.

5fill in blank

hard

Fill all three blanks to select cities with average temperature above 20, count of days above 10, and max temperature below 35.

PostgreSQL

SELECT city, AVG(temperature) AS avg_temp, COUNT(*) AS hot_days, MAX(temperature) AS max_temp FROM weather GROUP BY city HAVING AVG(temperature) [1] 20 AND COUNT(*) [2] 10 AND MAX(temperature) [3] 35;

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

A>

B>=

C<

D<=

Attempts:

3 left

💡 Hint

Common Mistakes

Using WHERE instead of HAVING for aggregate filters.

Using wrong comparison operators causing incorrect results.

The HAVING clause filters cities where average temperature is above 20, count of days is at least 10, and max temperature is below 35.