Counting
You are interested in figuring out where the customers of eSymphony are ordering from. Specifically, you want to know from how many different U.S.A. orders are coming in.
To calculate this you will need to include a filter to your data before applying the correct group function. Let's start building this query!
Cet exercice fait partie du cours
Introduction to Oracle SQL
Exercice interactif pratique
Essayez cet exercice en complétant cet exemple de code.
-- Count the number of billing cities
SELECT ___(___)
FROM ___
-- Filter on rows where the billing country is the USA
WHERE ___