Total Stock
Find total stock of all 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.
The task
Find total stock of all products.
A correct answer returns 1 row with one column: SUM(stock).
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
| id | name | category | price | cost | stock | sku | status | rating | review_count |
|---|---|---|---|---|---|---|---|---|---|
The first rows of each table are shown. See how all the tables relate on the database schema page.
Expected output
| SUM(stock) |
|---|
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
SUM stock
Show the step-by-step approach
How the model solution is built, in the order the database evaluates it:
- Read from the
productstable. - Aggregate over all the rows that are left: compute
SUM(stock). 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(*).
Related SQL challenges
- Find the Lowest Price with MIN()Similar levelEasy
- Find the Highest Price with MAX()Similar levelEasy
- Summarise Each Order: Total Quantity and AmountHarderMedium
- Calculate the Average Price with AVG()Similar levelEasy
- Add Up Order Totals with SUM()Similar levelEasy
Keep learning
- Lesson: Aggregate Functions
- All SQL practice challenges, by difficulty and topic
- SQL interview questions with answers
- SQL Playground: run any query on the same database