meaningful can be in context: - a UUID floating alone in an ocean of text has no meaning. - a UUID in a unique (indexed?) field of a relational database has meaning - it is the some identifier - 'Joe' has no meaning, except in context. You might expect that it is a name, but.. Hey Joe, get me some Joe!
:) On Wed, 8 Nov 2017 17:08:10 -0600, Keith Culotta via 4D_Tech wrote: > Something that stood out in a recent thread about the definition of > the Relational Model was a statement that said related fields should > contain meaningful information. This was a surprise, especially > since the use of UUIDs has been such a convenience. I took > 'meaningful' to imply 'user definable' (with guidance of course), in > spite of the headaches it can lead to. > > Keith - CDI > >> On Nov 8, 2017, at 4:48 PM, Chip Scheide via 4D_Tech >> <[email protected]> wrote: >> >> ** NO ** user definable data should be used as relational/unique key >> value. >> generate your own internal values for relations, longint, UUIDs, >> variations on the Batman Logo, anything that the user has no say in >> what it is nor how it is used. >> >> On Wed, 8 Nov 2017 17:38:38 -0500, Chip Scheide via 4D_Tech wrote: >>> >>>> If, as is the case in my situation, one has a unique field in the >>>> Employee table that is user recognizable such as an Employee Number >> As I suggested, the employee number could change, be reused, they could >> change the form of the ID, from say 10 digits, to a 4 character >> alphanumeric, or to a retinal scan... who knows!!! And don't forget >> that value will likely be typed (entered) at some point and there are >> typos too. >> >> Melinda Enters Joe's ID as 1234578 (which is Fred's), instead of >> 1234587. It takes a month to find the issue (payday) as Joe doesn't get >> a pay check and Fred gets an extra large one (way to go Fred! good work >> here is a bonus). I think you can see where this goes...how do you >> untangle *that* mess as all of your internal data is tied to the >> mis-entered employee ID. >> >> my 2cents >> >> >> >> --------------- >> Gas is for washing parts >> Alcohol is for drinkin' >> Nitromethane is for racing >> ********************************************************************** >> 4D Internet Users Group (4D iNUG) >> FAQ: http://lists.4d.com/faqnug.html >> Archive: http://lists.4d.com/archives.html >> Options: http://lists.4d.com/mailman/options/4d_tech >> Unsub: mailto:[email protected] >> ********************************************************************** > > ********************************************************************** > 4D Internet Users Group (4D iNUG) > FAQ: http://lists.4d.com/faqnug.html > Archive: http://lists.4d.com/archives.html > Options: http://lists.4d.com/mailman/options/4d_tech > Unsub: mailto:[email protected] > ********************************************************************** --------------- Gas is for washing parts Alcohol is for drinkin' Nitromethane is for racing ********************************************************************** 4D Internet Users Group (4D iNUG) FAQ: http://lists.4d.com/faqnug.html Archive: http://lists.4d.com/archives.html Options: http://lists.4d.com/mailman/options/4d_tech Unsub: mailto:[email protected] **********************************************************************
