Ordering
Eliminating duplicate results
Aggregation
14. Find the average value
Grouping
HAVING: filtering and ordering groups
Let's practice

## Instruction

OK, now that you know what best salary is, let's discuss another function:

SELECT
avg(total_sum)
FROM orders
WHERE customer_id = 100;


The function avg() finds the average value of the specified column.

In our example, we'll get the average order value for the customer with id 100.

## Exercise

Find the average salary in the table employees for the year 2013.

### Stuck? Here's a hint!

Type:

SELECT
avg(salary)
FROM employees
WHERE year = 2013;