Query Dojo vs Learn SQL

Walk into your SQL interview ready. Query Dojo is SQL interview practice that fits in a few minutes a day. Drill the classic questions, rehearse under a real interview clock, and see exactly what is wrong when a query fails. PRACTICE THE CLASSIC QUESTIONS 85 interview-style SQL challenges, from finding the runner-up salary to top earners per department, monthly retention, login streaks, running totals and medians. Every query runs on a real database, right on your phone. REHEARSE UNDER A REAL CLOCK Timed mock interviews: 25 minutes, 4 questions, no hints. Finish with a readiness score out of 100, so you know where you stand before the real thing. SEE EXACTLY WHY AN ANSWER IS WRONG Every run is checked against the expected result. When it is off, you see what is missing or extra, from columns to rows. Hints and full solutions are there when you are stuck. BUILD QUERIES WITHOUT A KEYBOARD Tap tiles to build real queries, put lines in the right order, or type from scratch. RELEARN WHAT YOU FORGOT 79 bite-size lessons, from SELECT and JOINs to window functions, CTEs, gaps and islands, and finding the median. A PLAN FOR YOUR LEVEL Tell us where you are and get a 4-week belt plan with the topics to focus on first. EARN YOUR BLACK BELT Every challenge and lesson moves you up, from white belt to black belt and beyond, with streaks to keep you consistent. A PLAYGROUND FOR EVERYTHING ELSE Run any SQL against 4 sample databases. Every run is rolled back, so experiment freely. Query Dojo Premium is an auto-renewing subscription, billed monthly or yearly. Payment is charged to your Apple ID at confirmation. It renews automatically unless canceled at least 24 hours before the end of the current period, and you can manage or cancel it in your App Store account settings. Terms: https://querydojo.pages.dev/terms Privacy: https://querydojo.pages.dev/privacy

Open the case file. The evidence is in the database. Learn SQL for free through 100 authored leads and 10 complete investigations. Read the brief, inspect the schema, write a real query, and use the returned rows to prove what happened. Each lead gives you a question and a working dataset. Run your SQL, study the result, revise your approach, then verify the finding when the evidence fits. Every investigation is authored, so the clues, datasets, and conclusions belong to a complete case. WORK 100 AUTHORED LEADS Ten investigations take you from the foundations to advanced analysis: • SELECT, WHERE, ORDER BY, and LIMIT • COUNT, SUM, AVG, GROUP BY, and HAVING • INNER JOIN and LEFT JOIN • Subqueries and CASE expressions • Window functions and common table expressions BUILD PRACTICAL SQL JUDGEMENT • Turn a case objective into a query • Explore tables and relationships through the schema • Read returned rows instead of guessing from syntax • Use clear feedback to correct a failed investigation • Reopen filed leads and improve your solution START WHERE YOUR SKILLS FIT New to SQL? Begin with Case 001 and learn the query desk step by step. Already comfortable with the basics? Choose a later investigation and meet a harder set of evidence. Archie, your SQL Case Guide, can offer a focused hint when you are stuck. Academy field guides explain the underlying concepts, while the Skill Map shows how each investigation builds your SQL toolkit. THE CURRICULUM STAYS FREE All 100 authored leads and the complete SQL learning route are free. There is no subscription. Start without an account, and keep your learning progress and settings on your device. Analytics can be disabled in Settings. Query verification, Archie guidance, verification links, and purchase restoration require an internet connection. An optional one-time Supporter purchase helps fund future investigations. It never limits the curriculum. Your first case is waiting.