Contact
Tell us what you need
Report a grading bug, suggest content or ask about your account — we read every message.
Support emailhello@datahoc.devInclude the lesson or problem URL when reporting a bug so we can check it faster.
You can write about
- A grading result that looks wrong, or an error when running a query.
- Lesson content that is unclear, misspelled or missing an example.
- Sign-in problems, forgotten passwords or progress that does not update.
- Topics, datasets or skills you would like to see next.
Response time
We usually reply within 2 business days. Grading bugs that affect scores are handled first.
Frequently asked questions
- Is DataHọc free?
- Yes. Every course and practice problem currently available is free; you only need an account to save progress.
- Do I need to install anything?
- No. The SQL editor runs in your browser and submissions are re-graded on the server.
- Can I learn on my phone?
- Yes. The layout works on small screens; result tables and the navigation collapse to fit.