If you're saying that the folders being moved contain the actual alias files, then there should be no issue.
If you're meaning that the folders being moved contain the files that are being referenced by aliases on another hard disk, then you will have issues.
An alias file, created when you use "Make Alias" contains nothing, but it creates an entry in the files resource fork that stores the important information. It stores the full pathname of the original file, and also the i-node (physical location on disk in Unix).
So you can rename files that have aliases pointing to them, move them to other folders on the same disk, and the i-node is unchanged, so the alias will still work.
You can also re-save a file with the same name, and while the i-node may have changed, if the filename is identical to previous, with the same full pathname, ie. /PowerMacG4/Users/simon/Documents/lotto.xls then the alias will be smart enough to work out the file you mean, even if the i-node references nothing).
So to answer your query, if you move files to another external volume, the aliases that refer to these files will only still be valid if you rename the external volume to be the same name as the disk where the files originally came from. You may also have to rename the original disk to avoid confusion. This may not be what you want to do, so you would have to re-create all the aliases.
I've used this many times where I've swapped out a smaller disk (containing files / folders referenced by aliases on another disk), replaced it with a bigger disk, copied all the files back (using the Finder - it was a non-boot backup disk) and renamed it to the original disk name. All the aliases worked perfectly.
Message was edited by: Simon Teale
Originally said Desktop database, meant resource fork