SQL Playground

Yes — it's SQLite compiled to WebAssembly, running fully in your browser. Every query executes against a genuine SQLite engine, so JOINs, GROUP BY, subqueries, CTEs, window functions, and CREATE/INSERT/UPDATE/DELETE all behave exactly as they would on a server. Nothing is uploaded; the database lives in memory on your device and is gone when you close the tab (unless you export it).

Yes. Click 'Open .sqlite' and choose a SQLite file (.sqlite, .db, or .sqlite3) to load it locally — the schema panel updates and you can query it immediately. Because everything runs in your browser, your file is never sent anywhere. Use 'Reset' to return to the built-in sample database.

Everything SQLite supports, which is a large, standards-based subset of SQL: joins, aggregates and GROUP BY, subqueries, common table expressions (WITH), window functions, CASE expressions, and full DDL/DML (CREATE, ALTER, INSERT, UPDATE, DELETE). Note it's SQLite's dialect, so vendor-specific features from MySQL, PostgreSQL, or SQL Server may differ.