Re: Access as a RDBMS--why the multiple relationships?
Date: Fri, 14 Dec 2007 22:45:42 +0100
> I notice in Microsoft Access the relationship chart can, unlike most
> textbooks, have TWO, not just one, relationship arrows between
> tables. But I think (and I just want confirmation of this) that one
> of these two relationship arrows is bogus, and more like a query than
> a true relationship.
I think you have either misread/misinterpreted the textbook or have the wrong text book. I don't remember Access that well - does it really say "relationships"? Anyway the arrows depict foreign keys. There is nothing wrong with having more than one arrow between tables.
> Here goes:
[snipped stuff I could not parse]
> ... entity TABLE A has Primary Key PKA that migrates to entity TABLE B as
> a (manditory, and non-exclusive, but doesn't matter) Foreign Key FKB.
> ...I just want confirmation that the SECOND relationship above is simply
> a bogus construct of Access, akin to a query constraint of some sort,
> and not really a 'relationship' as defined by RDBMS theory.
You really should start reading.
You are making another serious beginners mistake: mixing terms from different realms so you end up with an incoherent mess before you get to your real question.
-- What you see depends on where you stand.Received on Fri Dec 14 2007 - 22:45:42 CET