AI engineering glossary · SQL databases
What is COUNT (aggregate function)?
Aggregate function (also called COUNT, SUM, AVG): A function that combines many rows into one value, such as COUNT, SUM, AVG, MIN and MAX. Except COUNT(*), they ignore NULL. Used with GROUP BY, they give one result per group; without it, one for the whole table.
Aggregate function: an example
SELECT AVG(amount) FROM orders; returns the mean order value across all orders.
Related terms
More SQL databases terms
Where you learn it
Aggregate function is part of the AI Engineering Program, which teaches it with notes, a hands-on lab and an exam. The first lesson is free.