EasySQL challenge #28COUNT

Total Products

Count total number of products.

The challenge runs on the SQLabHub practice database (SQLite) and uses the products table. You can solve it in the browser, with nothing to install.

Solve This SQL Challenge

The task

Count total number of products.

A correct answer returns 1 row with one column: COUNT(*).

Tables used in this challenge

`products` 120 rows

id INTEGER (PK) · name TEXT · category TEXT · price REAL · cost REAL · stock INTEGER · sku TEXT · status TEXT · rating REAL · review_count INTEGER

First 3 rows of the products table
id	name	category	price	cost	stock	sku	status	rating	review_count
1	Play Kitchen Deluxe	Toys	1786.38	589.51	257	SKU-000001	active	4	57
2	Micro-Cut Paper Shredder 8-Sheet	Office Supplies	907.93	281.46	131	SKU-000002	active	2.5	447
3	4K Dual Dash Camera	Automotive	568.89	204.8	176	SKU-000003	active	4.1	29

The first rows of each table are shown. See how all the tables relate on the database schema page.

Expected output

Expected output of the challenge
COUNT(*)
120

The complete result: 1 row. This is the output of the model solution on the practice database.

What you practise

Summarising many rows into one value with COUNT, SUM, AVG, MIN or MAX

Hint and approach

Try the challenge first. Open these only when you need them.

Show the hint

COUNT(*)

Show the step-by-step approach

How the model solution is built, in the order the database evaluates it:

Read from the products table.
Aggregate over all the rows that are left: compute COUNT(*). With no GROUP BY, the result is a single row.

Model solution

Checking your session…

What to watch for

Aggregate functions. Aggregates skip NULLs. AVG divides by the number of non-NULL values and COUNT(column) can be smaller than COUNT(*).