Re: why hierarchy?
Date: 26 Jul 2006 08:13:39 -0700
Message-ID: <1153926819.632938.113720_at_m73g2000cwd.googlegroups.com>
> "Codd had a bunch of ...fairly complicated queries," Chamberlin said. "And since I'd been studying CODASYL (the language used to query navigational databases), I could imagine how those queries would have been represented in CODASYL by programs that were five pages long that would navigate through this labyrinth of pointers and stuff. Codd would sort of write them down as one-liners. ... (T)hey weren't complicated at all. I said, 'Wow.' This was kind of a conversion experience for me. I understood what the relational thing was about after that."
Could someone demonstrate this experience by replicating the Food
Judging Example at www.dbfordummies.com/example/ex039.asp with RM?
To verify which method's underlying data model is more general, one can
observe the impact on existing schema/data/query when meeting future
unknown data requirements (to be proposed by someone else). Would
someone be willing to engage in this example?
Received on Wed Jul 26 2006 - 17:13:39 CEST