Re: The Network Data Model, foundation for Relational Model

"Ken North" <knorth2_at_deletethis.yahoo.com> writes:
> I've never heard the term "network model" DBMS in any context other than the
> CODASYL DBTG standard.

i was writing code for a "semantic network" DBMS (a network model with some additional characteristics) out at the los gatos VLSI group about the same time I was writing code for System/R ... the original RDBMS at research (research lab, bldg 28 was about 10 miles from the Los Gato VLSI lab, bldg 29 ... the bldgs were consecutively numbered i would guess based on when they were built, rather than strict physical proximity).

The 'semantic network" DBMS done by the VLSI tools group drew a lot from Sowa's work on semantic networks. There has also been various efforts over the years to map semantic networks into RDBMS technology ... frequently the intermediate layer represents a 10:1 performance overhead handling the semantic network representation to relational representation. however, quicky use of search engine turns up some number of explicit implementations.

a random reference turned up by search engine that happens to also mention medical informatics and UMLS semantic networks ... even tho there has been significant effort mapping UMLS semantic networks to rdbms over the years:
http://courses.mbl.edu/Medical_Informatics/2001/outlinesFall2001.html

-- 
Anne & Lynn Wheeler | http://www.garlic.com/~lynn/