SQL Practice 8/13

Capstone: total spent per customer

This is the query you'd actually write at a job: "who are our biggest customers?" It needs everything from this module - a JOIN to connect orders to the people who placed them, GROUP BY to bucket by customer, SUM to add up what each one spent, and ORDER BY to rank them.

None of these pieces is new. What's new is stacking them: join first, group the joined rows, aggregate within each group, then sort the final result. That order - join, group, aggregate, sort - is the shape of most real reporting queries, not just this one.

Same users and orders tables as the JOIN lesson.

Your task: for each user who has placed at least one order, return their name and the total amount they've spent (as total_spent), ordered from highest spender to lowest.

You'll practice:

Joining, grouping, and aggregating in a single query
Ordering by an aggregated column

-- Name and total spent per customer, as `total_spent`, highest spender first.
SELECT users.name, orders.amount FROM orders JOIN users ON orders.user_id = users.id;