I noticed that MariaDB is installed and I Ed to have MySQL installed. I don’t think it’s a simple thing to have them both installed side by side so I’d like to uninstall MariaDB first. But I think openSUSE LEAP installed it on OS install. Does it have data in the db that will break something if i uninstall it?
MariaDB is drop-in replacement for MySQL (by the original MySQL author), everything that uses MariaDB should work with MySQL as well and vice-versa.
The actual database files might not be compatible (any more) though.
Just install mysql-community-server, and it should replace mariadb automatically.
The question is why you want to do that though.
I think mariadb is considered superior, at least there are reasons why it got replaced by mariadb as default in openSUSE years ago.
Does it have data in the db that will break something if i uninstall it?
In a default install there is no data in the database, it is not even started by default.
So if you didn’t actually use mariadb yourself, there should be no problems.
Some applications might start an internal instance though, e.g. Amarok and Akonadi (both KDE applications) do and create a database in your home folder.
As mentioned, I don’t know whether the old database files will still work then. In the worst case, you’d loose them.
For Amarok, this affects the music database, Akonadi uses it as cache, there shouldn’t be any actual data in its database.
openSUSE itself does not rely on it, nor use it at all by default.
A project I’m working on requires it.
mariadb 10 is not guaranteed to be compatible with mysql 5.6 up; so if you have any data stored using mysql 10, use mysqldump to back it up; you can then restore it to mysql.