esqlite return "error = 21"

[Zabrane]

Hi @mmzeeman

We switched to the latest esqlite version yesterday (we were previously using 0.8.6 for years) and we started getting the following error:

This happens sporadically and under almost no load (not even during concurrent writes).
Do you have any idea what can lead to this?
Many thanks

. Erlang 26.1.2
. rebar 3.22.0 on Erlang/OTP 26 Erts 14.0.2
. OS: macOS Sonoma | Ubuntu 22.04 LTS

[mmzeeman]

Could it be SQLITE_MISUSE?

#define SQLITE_MISUSE      21   /* Library used incorrectly */

That can happen when a connection is shared between multiple processes/threads. Or that a query was already done or errored earlier.

Before 0.8 every connection had its own associated os level thread. It looks like you were already using the never version which uses dirty schedulers.

The later releases have been small fixes, and sqlite version updates.

[mmzeeman]

With version > 0.8 you must be really sure to serialize requests to SQLite. The plus side is that connections are now much more light weight.

[Zabrane]

@mmzeeman thanks a lot, that was it. The new version is much faster and the process who opens the DB originally closes it earlier than before.
Keep up the work ;-)

[mmzeeman]

👍

Thanks for your reply... It is always nice to hear from people using this library.