How It Works
Become a data detective in three steps. No prior experience required.
Pick an Investigation
Browse Cases by difficulty and SQL topic. Each is self-contained with real data and a mystery to crack.
Query the Database
Write SQL in the browser. No setup needed. Get hints from Chief Fox when you get stuck.
Crack the Case
Use your results to name the suspect and close the case. Earn XP and level up your rank.
Five Ranks.
One Journey.
Built for the way you
actually learn
Every case requires real SQL against real data. No multiple choice, no hand-holding.
Concepts appear when the story demands them. JOINs matter when suspects have alibis.
Progress from Recruit to Chief Detective across four structured case sections.
A separate timed feature: randomised mysteries where you name suspects and cite evidence.
"The alarm was disabled at 22:13. Find who entered within five minutes of that, and whether they were on shift."
FROM access_logs a
JOIN personnel p ON p.id = a.person_id
WHERE a.door = 'EVIDENCE_LOCKER'
AND a.event_time BETWEEN '22:08' AND '22:18'
Real Data. Free Exploration.
No case to solve, no pressure. Pick a dataset you care about and write freely. Seven real schemas, all running in your browser.
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One user's full 2025 listening history. 10,800 play events with skip rates and audio features.
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424 popular Steam titles with review scores, genres and community tags.