Recorder - External DB - What happens when unavailable?


I’m thinking about using my MariaDB server for everything Home Assistant records. Especially the Energy history.
My Home Assistant Supervised runs on a RPI 3B and my DB is on a (separate) virtualized server.

However, I am wondering something and did not find the answer in the doc or here. Apologies in advance if I missed it.
Here’s my question:

What happens if my DB is unavailable, let’s say for 1h?
Does HA buffer the data and commits everything as soon as the DB comes back to life (up to RAM limits obviously)?
Or is all data after the ‘commit_interval’ period lost?

Many thanks in advance!