Hacker News new | past | comments | ask | show | jobs | submit login

> it can emulate concurrent writes in WAL mode

Seems a bit unfair to call WAL mode emulation of "true" concurrent writes as I'm pretty sure a write-ahead-log (WAL) is exactly how other databases implement multiple concurrent writes. It's just always-on rather than being opt-in.




Well, but that's not really what it's doing. WAL1 mode in SQLite is different than in your typical RDBMS. WAL mode in SQLite is just getting the write path outside of the read path, but there is still only 1 write allowed at any given time. The "fake" concurrency is done by letting write transactions queue up and wait for the lock.

See [here](https://sqlite.org/wal.html) under "2.2. Concurrency" where it says:

> "However, since there is only one WAL file, there can only be one writer at a time."

SQLite is awesome, I'm a huge fan, but if you need to do lots and lots of writes, then SQLite is not your friend. Luckily that's a very rare application. There is a reason you never see SQLite being the end point for logs and other write-heavy applications.




Guidelines | FAQ | Lists | API | Security | Legal | Apply to YC | Contact

Search: