How to store messages on the chat server?

Question

MySQL

There was a need to store messages of users who communicate in a chat. Where to store them? In a DB, in a text file?

Answer 1

Well, of course, in the database.

Answer 2

And then what should be done with these messages?
How big is the load and the cost of missing messages?
If the load is small and you need the last 20 chat messages, I would store it in a file, and if the cost of loss is zero, then in the chat daemon's memory...