I restored a 500mb partition over a 1000mb partition.
Not really, we are still in the same terminology confusion/mixup.
You actually backed up a volume (and NOT a partition) and you restored a volume (and NOT a partition). The difference may be just the excess sector hosting the bootsector backup in the case of a NTFS volume, but a partition has the "added dignity" of a specific entry in a partition table (in the MBR or in an EPBR), or if you prefer a partition (as used in Windows) is BOTH the area on disk occupied by the volume AND the corresponding entry in a partition table.
You cannot "restore a 500mb partition over a 1000 Mb partition", you can restore a 500 Mb volume inside a 1000 Mb partition. (which is what you did, or to be more even more exact you restored the 500mb volume to the initial part of the allocated space for a 1000 Mb partition in the partition table), if you actually restored it over the corresponding partition entry would have been overwritten.
I know that I am picky, this is part of my "let us call things with their names" campaign, an exact terminology/set of definitions helps to avoid misunderstandings, it's years that I go around attempting (usually failing at it ) to put together a "common dictionary" to better exchange info, still JFYI: