I am not sure I understand your question.
udev determines how a device will be assigned according to the udev rules. In other words, udev determines weather it is hdc, hda, etc..... Then fstab assigns ownership, permissions, and mount point.
google udev tutorial
Hope this helps.
What do you need the info for anyways?
Also, one way to find the device assignment is
su
fstab -l
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