Validate a view matches its query

Create a customer_revenue view and prove it returns exactly the same rows as the ad-hoc query it encapsulates.

1. 1CREATE VIEW customer_revenue with columns customer_id, name, orders (count of non-cancelled orders) and revenue (ROUND(COALESCE(SUM(total), 0), 2)), LEFT JOINing orders with status <> 'cancelled' in the ON clause.
2. 2Write the same logic as a standalone SELECT.
3. 3Verify: SELECT COUNT(*) AS mismatches FROM (SELECT customer_id, name, orders, revenue FROM customer_revenue EXCEPT <standalone query>) returns 0.

• customer_revenue returns one row per customer with the expected values
• The last result set shows 0 mismatches
• The script uses CREATE VIEW and EXCEPT

• Every run starts from a freshly seeded database, so your script must include its own setup statements.
• Only the last result set of your script is compared, so finish with the verification query.