Privacy Policy
Last updated: July 6, 2026
Introduction
MasterSQL ("we", "our", or "us") operates the website at mastersql.sedihub.com. This Privacy Policy explains how we collect, use, and protect information when you use our free online MySQL playground and SQL tutorials.
We believe in transparency. This policy covers what little data we handle, how session isolation works, and what rights you have. We do not sell, share, or monetize your personal information.
Data We Collect
MasterSQL is designed to minimize data collection. We do not require accounts, emails, or any personally identifiable information. Here is exactly what we collect:
Session Data
Each time you use the playground, we create a temporary session that stores your SQL queries, selected database, and query history. This data exists only in your browser and on our server for a maximum of 30 minutes. After 30 minutes of inactivity, your session and all associated data are automatically and permanently deleted.
localStorage Data
We use localStorage in your browser to remember your preferences. None of this data is sent to our servers or shared with third parties:
| Key | Purpose | Retention |
|---|---|---|
| mastersql_theme | Remembers your dark/light theme preference | Until cleared |
| mastersql_session | Stores your current session ID | 30 minutes |
| mastersql_history | Saves your query history for convenience | Until cleared |
| mastersql_tabs | Remembers your open editor tabs | Until cleared |
| mastersql_sidebar_width | Stores your sidebar width preference | Until cleared |
| mastersql_tutorial_progress | Tracks which tutorials you have completed | Until cleared |
| mastersql_quiz_scores | Saves your quiz scores and completion times | Until cleared |
| mastersql_cookie_consent | Records your cookie consent preference | Until cleared |
Session Isolation
MasterSQL provides complete workspace isolation for each user. When you execute a SQL query, we create a dedicated MySQL user and database that belongs exclusively to your session. Other users cannot see your data, and you cannot see theirs. This isolation is enforced at the database level, not just the application layer.
Your session database is automatically dropped when your session expires (after 30 minutes of inactivity) or when you manually reset the playground. No query results, table data, or database schemas are retained after your session ends.
Third-Party Services
MasterSQL is hosted on Cloudflare Pages and uses Cloudflare Workers for our API. Cloudflare may collect standard web server logs (IP addresses, browser type, referring URLs) as part of their infrastructure. This data is handled by Cloudflare under their own privacy policy.
We do not use Google Analytics, Facebook Pixel, or any other third-party tracking services. We do not use cookies for tracking or advertising purposes.
Advertising
MasterSQL currently does not display advertisements. If we add advertisements in the future, our advertising partners may use cookies and similar technologies to serve relevant ads. This Privacy Policy will be updated to reflect any changes in our advertising practices.
Data Sharing
We do not sell, trade, or otherwise transfer your information to outside parties. Your session data is temporary and isolated. Your localStorage preferences stay in your browser. We have nothing to share because we collect almost nothing.
Children's Privacy
MasterSQL is not directed at children under 13. We do not knowingly collect information from children. If you are a parent or guardian and believe your child has provided us with personal information, please contact us so we can delete it.
Data Security
We implement reasonable security measures to protect the limited data we handle. All communication between your browser and our servers is encrypted via HTTPS. Session isolation is enforced at the MySQL database level. However, no method of electronic transmission or storage is 100% secure, and we cannot guarantee absolute security.
Changes to This Policy
We may update this Privacy Policy from time to time. When we make material changes, we will update the "Last updated" date at the top of this page. Continued use of MasterSQL after changes constitutes acceptance of the updated policy.
Contact Us
If you have questions about this Privacy Policy or our data practices, contact us at [email protected].