In Pro 2.0, I was VERY EXCITED to see the "New GUID" button when editing a feature that uses GUID's (not globalid!) to as a foreign key....so in testing...I hit the button, the GUID populated, then on to "Add New to Relationship" to add a row to the child table in the relationship. Hmmmm what happens if I hit the "New GUID" button again? A new GUID appears (Primary key in this case)...whoa...my relationship is gone. Yep...there is now an orphan row in the child table using the GUID from the first time I hit the green button.
What SHOULD be happening, is, if there is a parent/child relationship using the GUID, hitting that button should check/warn the user that there is already a child row in the related table OR, hitting that button a second time should update the related row GUID, OR, the button should be disabled if there's already a related row hanging off that GUID.
This is a problem in Arc Map too, I've seen folks recalculate the GUID several times ("I didn't think it worked the first time") and trying to hunt down orphan records in the related table.
