You code your application from scratch ?? If yes you can rewrite URL with router system like slim or you implement it by you self. And .htaccess
in rooms, you are the name and also you are roomnames to store names of rooms?? Is a duplicate persistence
Where's diff? SQL is a language or MySQL is SGBD.
Why roomnames??
history??
Best means??
Certification for doing what ??
The finality of this query is??
Is a server data??
In user table??