Free · Runs in your browser

Learn SQL.
Solve the puzzle

Every lesson is a puzzle from the Academy. Ask the data, follow the trail and prove what you know with a single query.

✔ From scratch✔ Nothing to set up

Hi! I'm Professor Owl. Shall we solve a puzzle together?

SELECT✦WHERE✦IS NULL✦IN✦BETWEEN✦LIKE✦ORDER BY✦LIMIT✦COUNT(*)✦GROUP BY✦HAVING✦JOIN✦CTE✦WINDOW✦SELECT✦WHERE✦IS NULL✦IN✦BETWEEN✦LIKE✦ORDER BY✦LIMIT✦COUNT(*)✦GROUP BY✦HAVING✦JOIN✦CTE✦WINDOW✦

🧩46puzzles in 3 paths

⏱️2timed challenges

🎓9certificates

Learning paths

Choose what you want to master

Start with SQL. Each path moves forward in short modules, with real data and nothing to set up on your computer.

🗄️

SQL

Available

Four modules, from your first SELECT to window functions, on a database that lives inside your browser. Each module ends with an exam and its certificate.

✓Queries and filters
✓Aggregates and cleaning
✓JOINs and subqueries
✓Window functions
✓Exams and certificates
✓Interview questions

Start the path →

puzzle_003.sql

SELECT name, access_time
FROM access_log
WHERE door = 'Basement'
  AND reason IS NULL;

nameaccess_time

Clara Vega22:47

✓ Puzzle solved · +75 XP

📊

Excel Available

A real spreadsheet in the browser: formulas, $ references, IF, VLOOKUP and text cleanup.

SUMIFCOUNTIFVLOOKUP

🐍

Python Available

Real Python in your browser: from your first variables to analyzing whole tables with pandas.

Lists and loopsFunctionspandas

Your progress

Small challenges, steady progress

Ten minutes a day is enough. Solve a puzzle, earn XP and watch your streak grow week after week.

@genius

💡 Curious

✓0solved🔥0days⚡0XP🎓0certificates

MTWTFSS

Next title: 📘 Apprentice · 0/100 XP

SQL · Module 1 · Beginner

SQL Fundamentals

Queries on a single table: choosing columns, filtering, sorting and counting.

0 of 10 · 0%

🧑‍🏫

Next challenge · PUZZLE 001

The erased blackboard

SELECT · +50 XP

Start →

🔒

PUZZLE 002

The missing microscope

WHERE · +50 XP

🔒

PUZZLE 003

The basement door

AND · IS NULL · +75 XP

🔒

PUZZLE 004

Night calls

IN · BETWEEN · +75 XP

🔒

PUZZLE 005

The mysterious alias

LIKE · +75 XP

🔒

PUZZLE 006

The podium

ORDER BY · LIMIT · +100 XP

🔒

PUZZLE 007

The smoke alarm

COUNT · +100 XP

🔒

PUZZLE 008

The library patron

GROUP BY · +125 XP

🔒

REVIEW 009

Review: the inventory

Module review · +100 XP

🔒

EXAM 010

Exam: SQL Fundamentals

Exam · +250 XP

🏁

Module 2 · Summarize and clean

Next goal

🗺️

Everything in sight

You always know which puzzle is next and how much is left.

🔥

Consistency that shows

Your streak grows with every day you practice.

💡

From Curious to Genius

Every puzzle adds XP toward your next title.

🧪

Freedom to experiment

In the free Lab you can experiment without fear of breaking anything.

When you want more

Practice your way

Experiment with your own data or test what you know against the clock.

🧪 Free Lab

Write whatever queries come to mind, with no brief or solution to match.

✓ Five sample datasets ready to query
✓ Upload your own CSV: it is processed on your computer
✓ Bar and line charts from your results
✓ Autocomplete for tables and columns

Open the lab →

⏱️

Challenges

Mysteries with several tables, a timer and a single accusation. Fresh data on every attempt.

→

Pricing

Free to start. One payment for everything.

No subscriptions: you pay once with PayPal and the content is yours forever.

Free

US$ 0

Module 1 of SQL and Excel with its certificate, one challenge, interview questions and the Lab.

Start for free

Pro · one-time payment

US$ 18.99

All paths, exams, certificates, challenges and interview questions, plus everything added later.

See the Pro plan →

Start today

Your first query
is one click away.

The puzzle “The erased blackboard” is waiting for you. No account or prior experience needed.

Start for free →

✔ Free to start✔ Works in any browser

Learn SQL.Solve the puzzle