You would need to show us the exact commands you used, but I think you will find that it exists somewhere.
One thing to keep in mind: As long as the source and destination are on the same physical device (eg a partition), nothing actually gets **moved**. In these cases, "mv" really means "rename".
Consider 2 examples: You have files named "fred" and "alice", and you have a folder named "stuff"
mv fred stuff **This renames ./fred to ./stuff/fred Thus fred now appears to have been moved into the "stuff" folder. (Note that "." is a synonym for "current directory")
mv fred alice **This renames ./fred to ./alice and thus appears to erase whatever was in alice. It's not however really erased---the old data in alice is still on the disk, but the sectors have just been released to the filesystem for re-use.
From the above, we see that--by default--mv can wipe out the target, but probably will not wipe out the source.