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SQL practice · Retail case · 15–20 minutes. Start with retail-setup.sql in a disposable local SQLite database.

Learn → Try → ExplainReviewed 2026-10-15

Your task

Create an audit showing status, count and amount. This supports reconciliation, not a second definition of revenue. Write the query before opening the solution. Record the expected output grain.

Hint

Apply the status filter before aggregation. State whether the result represents orders, channels or periods. Keep currency units explicit.

Worked solution

cancelled: 2 orders / 9000 cents; completed: 6 orders / 70000 cents. All source amounts total 79000 cents.

SELECT status,COUNT(*) n,SUM(net_cents) cents FROM orders GROUP BY status ORDER BY status;

Check your reasoning

Reconcile the result to the source and describe one limitation. This tiny fictional dataset cannot establish customer behavior or predict future sales.

Make the reasoning yours.

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