On Thursday, May 26, 2011 11:31:45 PM UTC-4, Bob Melson wrote: > > Y'all'd have to check the archives for the down'n'dirty, but Wes and I and > I don't remember who all else had a discussion of this very thing (_UID, > _UUID, _GUID) some time back. I contended then that UUID (Universal > Unique ID) and it's close kin, UID and GUID, meant that the number > assigned to Cousin Mortimer should be the same universally - here, there, > wherever it appears. Not so. The "universe" is the machine where the > data appears and on which the software resides by which the UUID is > generated and it's only there that it's guaranteed to be unique. Take > that same data to another machine or other software and, guess what?, the > Universal Unique ID will be different. Or, say, Mort's data changes - ta > DA, you may (or may not) get yet another UUID. > > The only use I can see for UUIDs is in determining the origin of a > particular record - if I publish Mort's data and include the UUID and some > time later find that Snively Whiplash has published the exact same data > with the exact same UUID and has claimed it to be his own, then I'll know > what to think about ol' Snively, won't I? > > Swell Ol' Bob > Bob, You were right and should have stuck by your guns!! I don't know where the others got the interpretation that a UID should be unique only within one database. This is certainly not a GEDCOM rule since GEDCOM doesn't even have the UID concept. Their interpretation can only be coming from some vendor's misinterpretation, so to treat that misinterpretation as if it were a rule or the way things should be is wrong. A UUID is intended to be unique for all time and place. If a vendor says they use UID's where the U means "universal" and they don't support this then they don't support UID. A program should not alter a UID value upon import. If it does, though, who really cares, since there's no way to take advantage of UID's in genealogy. So no wonder it doesn't matter to anyone (yet). Tom

On 05-27-2011 03:55, Tom Wetmore wrote: > You were right and should have stuck by your guns!! I may be misremembering, but I think the disagreement was that someone, perhaps Bob, thought that the UID would be a universal ID for a _person_ which could be used for that person in all databases. Others stated, no, it distinguihses a _record_ from other records that otherwise might seem identical. > I don't know where the others got the interpretation that a UID should > be unique only within one database. This is certainly not a GEDCOM rule I don't recall seeing that interpretation. -- Wes Groleau There are two types of people in the world … http://Ideas.Lang-Learn.us/barrett?itemid=1157