Most coding education has a gap.

You write a SQL query. You see the result. But between the query and the result, something happened - rows were scanned, filtered, joined, grouped, sorted. That process is where the actual learning lives, and it's usually invisible.

I built Qatabase to close that gap.

SQL Flow

Write any SQL query and SQL Flow will show you how it executes:

• Watch rows pass through WHERE filters
• See which rows match during a JOIN (and which don't)
• Watch groups form during GROUP BY
• Trace window function partitions and ordering

It turns abstract concepts into something you can observe.

Python Flow

Same idea for Python:

• Variables update in real time as code runs
• Data structures (lists, dicts, sets) are visualized
• Call stacks are shown during recursion
• Algorithm behavior is animated (sorting, searching, graph traversal)

The curriculum

40 courses. 1,000+ exercises. Everything is sequential.

SQL (20 courses): First Steps through DDL/DML, covering joins, subqueries, window functions, CTEs, JSON, query optimization.

Python (20 courses): Fundamentals through ML Foundations, covering OOP, algorithms, NumPy, Pandas, data cleaning, visualization, statistics.

Plus interactive visualizers for probability and statistics (Bayes' theorem, CLT, hypothesis testing, ROC curves, and more), 29 educational games, and an algorithm visualizer.

Beyond courses

I didn't want to stop at just exercises. Learning needs structure, goals, and proof of progress.

Guided projects -- build real applications in a multi-file workspace. Templates include building a vector database from scratch, a RAG pipeline, a Prompt Engineering Lab, an API data dashboard, and more.

Skill roadmap -- a visual career progression map for SQL and Python. It shows which courses lead to which certificate tiers, and which job roles each tier unlocks. From Junior Developer to ML Engineer, you always know where you stand.

Certificates -- three tiers (Associate, Professional, Expert) for SQL and Python tracks. Each certificate has a unique verification ID. Complete the required courses, claim your certificate.

Masterclass courses -- deep-dive video content on Oracle architecture, ML, and AI for when you want to go beyond exercises.

Try it

Free tier: first 3 SQL + 1 Python course, all visualizers, all games, full roadmap. No time limit, no credit card.

Pro ($24/month or $12/month billed yearly) unlocks all 40 courses, projects, masterclass, and certificates.

https://qatabase.com

I'm actively building more courses and would love feedback from the dev community. What topics should I cover next? Do the certificate tiers match what hiring managers actually look for?