Re: A foreign key on a self-referring table
Date: Mon, 8 Mar 2004 19:01:34 +0100
Message-ID: <c2icdt$1rrk12$1_at_ID-184953.news.uni-berlin.de>
m> Before I start nitpicking, let me compliment you on your very m> informative answer. I learned about databases when m> nobody claimed relational databases were available. m> A change of job made me need to revive and refresh my knowledge. m> One way of doing that is reading this newsgroup. m> Valuable posts like yours make that a worthwhile effort. m> Yet I will snip most of it. Just take that as an agreement m> of sorts.
Thank you for the kind words, I've only started reading Date's book since a couple of years and I still have to learn a lot from them.
Your remarks have been very valuable to me, and I just realized that my answer was too much imprecise and oversimplified.
I will just snip most of your remarks because I fully agree with them.
First of all I should have given names to relations and should have given evidence of keys.
Secondly naming the hierarchy "organization chart" was really a bad move (I could have though a bit more for something else).
I also agree it shouldn't be modeled like this in a real database, and I would never do it in such a simplified manner.
It is very true, for example, that a position can be vacant or that a manager can be responsible of more departments (happens a lot with ad-interim assignments for short to medium periods).
Thanks for pointing them out, I'll try to be more precise and less simplicistic next time.
Gianluca. Received on Mon Mar 08 2004 - 19:01:34 CET