SQL playground
Run a SQL query against a CSV file — SELECT, WITH, DESCRIBE or SUMMARIZE — entirely on your device.
This page always downloads the big-file engine, even for a small file — the engine is what runs the query. It downloads once and then stays on your device.
What this box can run
- Read-only: SELECT, WITH, DESCRIBE and SUMMARIZE only.
- One statement at a time.
- Reads only the file you opened here — never a network address.
- Runs on your device — nothing about your file is uploaded.
Run a SQL query against a CSV file — SELECT, WITH, DESCRIBE or SUMMARIZE — entirely on your device.
About this tool
What you provide
- One CSV or TSV file.
What you get
- Up to 100 rows of the query's result at a time, with the column names the query produced.
- For a result with more than 100 rows, the exact range shown and how many rows came back in total.
Limits
- Read-only: only SELECT, WITH, DESCRIBE and SUMMARIZE statements run — anything that changes data or the database itself is refused before it reaches the engine.
- One statement at a time, and only against the file you opened here — never a network address.
- Reading the file needs a one-time database-engine download of about 7 MB, downloaded even for a small file because the engine is what runs the query.
- Everything runs on your device and nothing about your file is uploaded.
How to use it
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Choose a CSV file
Tap “Choose a CSV file” or drop a .csv or .tsv file onto the box — the playground opens it as a queryable table.
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Download the engine
Tap “Download the engine (~7 MB)” — it downloads once and stays on your device for every file after that.
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Run the seed query
Your file opens as a table with the same name, and the box is filled with a starting query — tap “Run” or press Ctrl + Enter.
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Write your own query
Edit the box with SELECT, WITH, DESCRIBE or SUMMARIZE and run it again — a query that changes data is refused with an explanation instead of running.
Frequently asked questions
Why does this page ask me to download an engine even for a small file?
The playground always uses the same database engine to run your query, whatever the file's size — the download happens once, then stays on your device for every file after that.
What can I actually run in the box?
Only SELECT, WITH, DESCRIBE and SUMMARIZE — one statement at a time, against the file you opened here. Anything that would change data or the database itself is refused before it runs.
Why was my query refused?
The box explains which rule it broke — an empty query, more than one statement, a keyword that changes data, a network address, or an unclosed quote — alongside the exact part of your query that triggered it.
Does running a query upload my file anywhere?
No. The file is read on your device by the downloaded engine, and nothing about it — or your query — is sent to a server.