Free SQL online compiler

SQL playground wired to practice

Try SELECT logic quickly, beautify with the SQL formatter, generate mock rows, then prove query skills on the SQL coding track.

Open SQL runner SQL coding Problems explorer

1 Try Run SQL
2 Tool Format & mock
3 Prove Coding / assess

SQL scratchpad

Free run — no login. Rate-limited. Same runner as the multi-language hub.

Source

SELECT 'Hello from Toolliyo Playground' AS greeting;
SELECT 1 + 2 + 3 + 5 + 8 AS fib_sum;

stdin (optional)

Output

Press Run to execute.

After you try SQL

Database academy SQL coding Problems explorer

How to use this SQL compiler

Write a SELECT (or small script) in the scratchpad.
Optionally format first with the SQL Formatter tool.
Run and read the result set / errors.
Open SQL coding problems when you want judged exercises.

Tips

Use Mock Data Generator to invent tables mentally before writing joins.
Prefer clear aliases — interviewers care about readable SQL.
Database tutorials cover MySQL / Postgres depth after you prototype here.

Tools for this stack

Format, mock, or diff — then come back and re-run.

Full toolbench

SQL Formatter Beautify queries, then run them in the SQL scratchpad. Mock Data Generate CSV / JSON / SQL rows for local experiments. JSON Formatter Pretty-print API payloads before you paste them into code.

SQL playground FAQ

Which SQL dialect is this?

The runner uses a lightweight SQL engine suitable for SELECT experiments. Dialect-specific features may differ from production MySQL/Postgres/SQL Server.

Can I create tables?

Keep queries simple. For schema-heavy drills, use coding-practice SQL problems with prepared schemas.

What is Try → Tool → Prove for SQL?

Try a query, format/mock in tools, then prove on SQL problems or the problems explorer.

Toolliyo Assistant

Ask about tutorials, ebooks, training, pricing, mentor services, and support. I use public site content only—not admin or internal tools.

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