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 <4d_tech@lists.4d.com> > 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:4d_tech-unsubscr...@lists.4d.com > ********************************************************************** ********************************************************************** 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:4d_tech-unsubscr...@lists.4d.com **********************************************************************
