Doing a video/music database export (when things are running okay) always works as a good backup system.
A remote SQL database you can always backup via sqldump or tools like PHPMyAdmin. And don't forget to include commands to recreate the tables.
If you are familiar enough with SQL, then you can edit/change the paths in the various (4?) database tables.
Yeah, you are right. Backup system is a good advice.
To say true for the moment I feel not familiar enough changing the SQL database table, but hope I can learn this. And I will make a backup before trying to change it.
So thank you for the advice.