It might be my memory, but I do not think that is how it worked in the beginning I was working on relational model dbs before SQL was a language
Rdb at DEC for example. That was one of the ket differences between model types how you created and maintained the relations. I do not believe that there was even a thought of primary keys Regards Chuck ------------------------------------------------------------------------------------------------ Chuck Miller Voice: (617) 739-0306 Informed Solutions, Inc. Fax: (617) 232-1064 mailto:miller.cjay<AT SIGN>gmail.com <http://gmail.com/> Brookline, MA 02446 USA Registered 4D Developer Providers of 4D and Sybase connectivity http://www.informed-solutions.com ------------------------------------------------------------------------------------------------ > On Aug 7, 2017, at 12:14 PM, steve simpson via 4D_Tech <[email protected]> > wrote: > >> >> >> On the other hand, you do model the data after business relations, but the >> keys that tie that relation data need/should never be seen in a well >> designed system. If a user readable key is needed by business, then there >> should be another data piece that the user can read (like an MRN, medical >> record number, or an abbreviation that is unique and human readable) But >> these should never be used to link together data in a structure in primary >> key foreign key relation. >> [snip] >> >> >> > +1 My point exactly, only stated much better. ********************************************************************** 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] **********************************************************************
