I've had it installed before when using nextcloud, but removed it. It's still there in appdata/mariadb/, and I see it takes up half of my cache drive. So I'd like to delete it, but I don't know if I dare.

It's not installed by default right? Everything in appdata is supposed to be put there by ME adding a docker?

(Just realized every single docker I've tried out still lingers in the appdata)

I just deleted everything in appdata not installed anymore. Still works. I'll kick this open if it dies at reboot.

yes appdata/mariadb/ is needed! This is where the file database write itself. if the docker image becomes corrupt or delete you lose the entire mysql database...

this is why its important to map and volume map docker data to a physical file path so it doesn't bloat the docker image, and you don't lose everything in your docker for use else where.

to remove a docker and its data complete you need to stop the docker. Delete the docker and check the box to remove the docker image. and if volume mounts and data paths were used clear out any existing configurations.

Edited September 21, 2025Sep 21 by bmartino1

Correct me if I'm wrong, but I believe the OP has removed his Nextcloud docker, and MariaDB was installed during his setup of Nextcloud.

So unless he is sharing MariaDB with another docker application on his server, neither the MariaDB container nor its appdata is needed.

Edited September 21, 2025Sep 21 by ConnerVT
speeling

3 hours ago, bmartino1 said:

yes appdata/mariadb/ is needed! This is where the file database write itself.

It's not since as they said they're not using mariadb anymore.