About SqlInt

SqlInt (sqlint.com) is a browser-based SQL practice and interview-preparation platform that also provides free client-side SQL tools for developers. Practice questions, puzzles, and case studies are solved in an in-browser SQL editor with instant feedback, and a suite of free utilities — formatter, converters, visualizers — runs entirely on the client. SqlInt is an independently operated service based in India.

• 95+ SQL interview questions with schemas, hints, and an in-browser editor that executes your query and compares results instantly.
• 16 story-driven SQL puzzles that teach SQL through narratives — solvable on SQLite or PostgreSQL engines.
• 20 case studies built on real business scenarios — churn analysis, fraud detection, revenue analytics, and more — with full schemas, datasets, solutions, and explanations.
• A 27-topic learning roadmap from your first SELECT to window functions, indexes, and analytics SQL, with syntax, examples, common mistakes, and interview tips.
• 11 free browser-based tools: SQL formatter, CSV to SQL, JSON ↔ SQL, JOIN visualizer, data anonymizer, data type mapper, LIKE tester, SQL minifier, case converter, UUID/test-data generator, and timestamp converter.
• Practical SQL articles and references on query patterns, performance, security, and interview preparation.
• Progress tracking (solved and visited stats) across questions, puzzles, and case studies on a free account.

Students and job-seekers preparing for SQL interviews; data analysts and data engineers refreshing or sharpening their SQL; and developers who want quick, no-install SQL utilities — formatting, conversion, anonymization, join exploration — without signing up or installing anything.

• Practice questions run inside your browser: SQL is executed locally by a WebAssembly database engine — SQLite (via sql.js) for practice questions, and PostgreSQL (via PGlite) for puzzles. Results are compared against reference solutions instantly.
• The mini tools also process input locally in the browser. Pasted SQL, CSV, or other data is processed on your device and is not uploaded to SqlInt's servers for processing.
• A free account is only needed to save progress and access premium content — the mini tools work without signup.
• Purchases are processed by Razorpay, a third-party payment provider.

• Queries actually execute. Practice against a real database engine running in your browser — SQLite for questions and real PostgreSQL via PGlite for puzzles — with automatic result comparison, instead of multiple-choice quizzes or read-only tutorials.
• Story-driven puzzles. A narrative puzzle format that teaches SQL through playable scenarios.
• Real-dataset case studies. Full business scenarios with schemas, datasets, solutions, and explanations.
• A structured path. A 27-topic roadmap that takes you from basics to interview-level SQL in a defined order.
• Free, private tools. Client-side processing means pasted data is never uploaded for processing, and every tool works without an account.
• Nothing to install. Everything runs in a modern browser.

• The practice engine currently supports SQLite and PostgreSQL. It is not a MySQL or SQL Server practice environment.
• The mini tools are focused single-purpose utilities — not full IDEs, database clients, or data-pipeline products.
• An internet connection is needed to load the site and its WebAssembly engines; after loading, query execution and tool processing run locally.
• Some questions, puzzles, and case studies require a paid pack (see below).

SqlInt is free to start. A starter pack is included free, forever, and the learning roadmap and all 11 mini tools are free without an account. Premium packs unlock the full question bank, all puzzles, and all case studies, with monthly or yearly access options priced in Indian rupees.

SqlInt is an independently operated service based in India. For questions, feedback, or privacy requests, email support.sqlint@gmail.com or use the Contact Us page. See also our Privacy Policy and Terms of Use.