Re:Free SQL→ER diagram tool, runs in the browser, nothing up...
by __natty__ on Sunday June 14, 2026 @04:31AM
(#48525333)
Truely good work! It’s responsive, clean and “onboarding” experience without signup walls is great. Good job.
Re:Free SQL→ER diagram tool, runs in the browser, nothing up...
by Hendrikto on Sunday June 14, 2026 @05:15AM
(#48525526)
> The URL contains the entire schema.
Isn’t that going to be a problem due to the URL length limitations?
> It is RECOMMENDED that all senders and recipients support, at a minimum, URIs with lengths of 8000 octets in protocol elements.
Re:Free SQL→ER diagram tool, runs in the browser, nothing up...
by johndough on Sunday June 14, 2026 @05:44AM
(#48525685)
Probably not that important in practice. Firefox allows 2^20 - 4 and Chrome allows 2100000 characters. Also, 8000 characters already allows for an unreasonable amount of SQL and could be extended even further with compression. And if that should not be enough, the website already supports JSON exports. All in all, this seems like a worthwhile tradeoff for not having to store anything.
No backend, no accounts, no data leaving your machine.
A few implementation details that were fun:
* Built on <canvas> instead of DOM/SVG. Tables are rasterized into cached bitmaps with viewport culling, which keeps things smooth even with hundreds of tables on screen.
* The SQL parser tracks source spans for every token. That lets edits stay surgical so a rename a table and only the relevant identifier (and its references) change while comments and formatting remain untouched.
* The URL contains the entire schema. Sharing simply serializes the schema into the URL itself, so there's no backend, no stored state, and no account required.
* I also experimented with a Rust/WASM version because why not? but the parser was ~37% slower because the JS↔WASM boundary cost outweighed the compute savings but The O(n^2) overlap-resolution pass was about 2.2x faster though * In the end I stuck with plain JavaScript. No framework ~32KB gzipped