Connection between filesystem and disc

I understand that if I label my filesystem Data, then, on boot, the physical disk is identified as dev/sda the partition on it is sda1 and a symlink to /dev/sda1 is created in /dev/disk/by-label/Data

Thus persistent block device naming.

Then when the fs is mounted a directory /srv is created and the mount point is /srv/dev-disk-by-label-Data/

I don't understand how this mount point is linked to /dev/disk/by-label/Data which would then be linked to /dev/sda1

I think the answer is the filesytem table /etc/fstab

This has been edited by OMV and ties my fs identifier /dev/disk/by-label/Data to the mount point for that file /srv/dev-disk-by-label-Data .

So when the fs is mounted, the system knows which fs it is, and the fs is identified via symlink to /dev/sda1