SQL Explainer

Translate SQL queries into plain English descriptions with clause-by-clause breakdown.

freeworks offlinenothing uploaded
Input
Output
—

About sql explainer

SQL Explainer is one page doing one thing. No account, no settings to sync, no history building up somewhere.

The tool is a few kilobytes of JavaScript, not a service. That is why it can promise your data stays put and actually mean it.

You will find it under SQL & databases, alongside 27 other tools for the same sort of job.

Explains SELECT, JOIN, WHERE, GROUP BY, and subqueries.

How to use it

01
Start it
Every control is on the tool itself. Keyboard shortcuts, where there are any, are listed beside it.
02
Watch it run
It updates in the page as you go. Nothing is sent anywhere, so it keeps working with the network off.
03
Close when done
Nothing is stored between visits. Reloading gives you a clean start rather than picking up where you left off.

Examples

Explain SELECT with JOIN
Get a plain English explanation of a SELECT query with JOIN and WHERE
Input
SELECT u.name, COUNT(o.id) as order_count FROM users u LEFT JOIN orders o ON u.id = o.user_id WHERE u.active = true GROUP BY u.name HAVING COUNT(o.id) > 5 ORDER BY order_count DESC LIMIT 10
Output
This query retrieves data:
- Selects 2 column(s): u.name, COUNT(o.id) as order_count
- From the "users" table
- LEFT JOINs with "orders"
- Filters rows where: u.active = true
- Groups results by: u.name
- Filters groups where: COUNT(o.id) > 5
- Orders results by: order_count DESC
- Limits to 10 row(s)

Questions

Does SQL Explainer work offline?+

Yes. It is JavaScript running in this tab, so once the page has loaded it needs nothing further from the network. Put the machine in flight mode and it carries on. Nothing you do here is sent anywhere, because there is nowhere for it to go.

Does it remember anything between visits?+

No. Reload the page and it starts from nothing. There is no account, no saved state and no cookie holding your last session. That is a deliberate trade: it cannot lose your data because it never keeps any.

Is it accurate?+

Timing comes from performance.now(), the high resolution clock the browser provides, rather than from setInterval, which drifts by a few milliseconds every tick and compounds over minutes. What can still shift things is the browser throttling a tab in the background, so leave it visible if the timing matters.

Does it make a sound?+

Where a sound makes sense, it is generated with the Web Audio API rather than loaded as a file, so there is nothing to download and nothing to block. Browsers refuse to start audio until you have interacted with the page, which is why the first press is what switches it on.

Can I use SQL Explainer on a phone?+

Yes. The controls are sized for touch and the layout collapses to one column on a narrow screen. Bear in mind that a phone locking its screen will suspend the page, and timing stops with it.