Ordering
Limiting the output
Eliminating duplicate results
Aggregation
Grouping
HAVING: filtering and ordering groups
Let's practice
Instruction
That's right. The last function that we'll discuss is SUM().
Examine the example:
SELECT SUM(total_sum) FROM orders WHERE customer_id = 100;
The above instruction will find the total sum of all orders placed by the customer with ID of 100.
Exercise
Find the sum of all salaries in the Marketing department in 2014. Remember to put the department name in the single quotes!
Stuck? Here's a hint!
Type:
SELECT SUM(salary) FROM employees WHERE year = 2014 AND department = 'Marketing';
