SqlInt: SQL Practice & Interview Workspace

SqlInt: SQL Practice with Less Noise

Solve interview-style SQL problems, explore real-world case studies, play story-driven puzzles, and track progress — all in one clean workspace.

Free to start · Pro plans from ₹199/mo

Questions

Puzzles

Case Studies

Roadmap Topics

Challenges

to Start

Learning Roadmap

From zero to SQL expert

27 topics with syntax, examples, common mistakes, and interview tips

Beginner

7 topics
  • SELECT
  • WHERE
  • ORDER BY
  • JOINs

Intermediate

8 topics
  • Aggregates
  • GROUP BY
  • Window Functions

Advanced

8 topics
  • CTEs
  • Optimization
  • Indexes

Expert

4 topics
  • Analytics
  • Cohorts
  • Business SQL

SQL Playground

SELECT name, role, salary
FROM employees
WHERE salary > 70000
ORDER BY salary DESC;

Filter rows with WHERE

namerolesalary
Aisha KhanData Engineer92000
Ravi MenonAnalyst78000
Sara LeeAnalyst74000

3 of 8 rows match — try it live in the playground.

Open the free playground

Write a query.
See the answer in milliseconds.

  • Instant result comparisonRun a query and immediately see your rows against the expected output.
  • Runs entirely in your browserSQLite via WebAssembly — no installs, no backend round-trips, no setup.
  • Schema, hints & solutionsEvery question ships with the full table setup, progressive hints, and a reference solution.

Mini Tools

SQL Tools — Free, in your browser

No signup, no backend round-trips — format, convert, and generate right on the page

Catch anti-patterns, style issues, and risky constructs before they ship

Open SQL Linter

SQL Linter

Ship cleaner SQL — catch anti-patterns before review.

  • Flags SELECT *, implicit comma joins & missing WHERE clauses
  • Lint-as-you-type with clickable line:column diagnostics
  • 7 dialects — Postgres, MySQL, BigQuery, Snowflake & more

Beautify messy queries in 7 dialects

Open SQL Formatter

SQL Formatter

Turn messy one-liners into readable queries in a click.

  • Live preview across 7 dialects incl. BigQuery & Snowflake
  • Keyword case, indentation & comma-position controls
  • Sample query pre-loaded — try it with zero pasting

See how INNER, LEFT, RIGHT & FULL work

Open JOIN Visualizer

JOIN Visualizer

Finally see what each JOIN actually returns.

  • INNER, LEFT, RIGHT, FULL & CROSS with live result rows
  • Venn diagram updates as you change the join type
  • Editable tables — add rows, columns, even a 3rd table

Ready to crack your next SQL interview?

Practice real interview questions right in your browser — instant feedback, story-driven puzzles, and a full learning roadmap. No setup required.

Free to start · Pro plans from ₹199/mo

// FAQ

SQL Practice — Frequently Asked Questions

How do I practice SQL for interviews?

Start with the free SQL practice questions, then work through the 27-topic roadmap and the story-driven puzzles. Every question includes a schema, hints, and an in-browser SQL editor with instant feedback — no setup or database installation required.

Is SqlInt free?

Yes — practice is free to start. You just need a free account to open the SQL editor and solve questions, which also keeps your progress saved. The complete 27-topic learning roadmap and all 12 mini tools work without an account, and optional Pro packs unlock the full question bank, all puzzles, and all case studies.

Which SQL engine do the practice questions run on?

Practice questions run on SQLite (via sql.js) and SQL puzzles on PostgreSQL (via PGlite), both executed locally in your browser. SqlInt is not a MySQL or SQL Server practice environment.

Do I need to install a database to practice SQL?

No. Everything runs in your browser through WebAssembly — the SQL editor, schema, sample data, and result comparison all work client-side, so you can practice instantly on any device.

What SQL topics should I focus on for a data analyst interview?

Prioritize SELECT and filtering, JOINs, GROUP BY and aggregations, window functions, and CTEs and subqueries. The roadmap marks each topic by level, and the interview-tip sections cover the exact patterns interviewers ask about.

What is the best way to practice SQL online?

The fastest way is to solve real problems in a real query editor. Start with easy filtered queries, then move to JOINs, aggregations, and window functions. SqlInt gives you an in-browser editor with instant result comparison, so every practice session builds directly toward interview questions.

Does SqlInt provide real SQL interview questions with solutions?

Yes. The question bank mirrors the patterns used in real data-analyst, data-engineer, and backend interviews — joins, aggregations, deduplication, window functions, and ranking problems. Every unlocked question includes a reference solution, an explanation, and progressive hints; the full premium bank is part of the paid challenge packs.

I'm a complete SQL beginner — can I use SqlInt?

Absolutely. Start with the 27-topic learning roadmap, which walks you from basics to advanced topics with examples, common mistakes, and interview tips for each level. Then apply what you learned on the easy practice questions and story-driven puzzles.