I wanted to be able to archive my catalog and its cataloged photos to another drive or computer without having to tell PMP that this has happened.
Lightroom does this very well as long as the catalog and the photos that have been cataloged are on the same drive. Lightroom accomplished this as follows:
File names and locations of cataloged files are stored in two tables: one table has the file name and other info about the file including a link to another table that stores the full unique paths for all folders in the catalog. This table also has a column that stores the path relative to the catalog.
It is the relative path item in the catalog that allows one to move folders of photos and the catalog to another drive or computer and work without a hitch PROVIDED the catalog is originally created on the same drive as ALL the photos in the catalog. It so happens that this is exactly how I had setup my directory structure.
As an example, here is a simplified tree of my directory structure:
2020 > Catalog > Photos > Canon M6 Mk II > Developed > Phone 2021 > Catalog > Photos > Canon M6 Mk II > Developed > Phone
As you can see, my Photos directory will always be relative to my catalog and hence if I copy my 2020 directory to another drive and then open the catalog it will be able to find my photos without me having to tell the catalog where they are.
It would be most useful if PMP could have a feature similar to this which will make it much easier to move the catalog and photos to other disks or computers.
So your request is to be able to move catalogs without having to use the Locate Existing Catalog button?
I was going to refer you to a forum thread on this for the more technical details, but I assume that was already you.