Dennis Lee Bieber <wlfraed@ix.netcom.com> writes: > On Fri, 01 Feb 2008 16:24:12 -0500, Haines Brown > <brownh@teufel.hartford-hwp.com> declaimed the following in > soc.genealogy.computing: >> A "relationship event" seems to conflate the categories. An "event" >> (in the sciences, anyway) refers to a change of state. Yet the >> child-mother relation is the _result_ of a birth event, but in itself >> does not refer to a change of state. Also, who are the principles in >> the case of a person's death? To presume that the death was witnessed >> seems unwarranted. >> > I'm an old Ultimate Family Tree user, where the data entries > were called "events", and the parents were roles in the birth event > (three common roles: child [the person whose birth is recorded in the > event], father, mother.. Could also add midwives, doctor, etc.) > > TMG documentation refers to the data entry as a "tag"... So > birth is a tag, relationship is a tag, death is a tag... Obviously I was confused by TMG's proprietary meanings. Data entry seems to define a steady state, rather than event in the sense we normally use the word. The term "role" refers to a functional relation, but for it to generate an event it must be a causal relation. GEDCOM includes functional relations, but not event-generating causal relations. Allow me (who is profoundly ignorant) to speculate. There seems to be something we might call states (data as it applies to an individual and also formal relationships among individuals as in a family). Such data can be stored readily in a flat file. On the other hand, there are also events (in the sense of changes of state), which are the effect of a causal rather than a formal relation of individuals, which therefore can't be represented in a flat file. These two contradictory aspects are interdependent. An event changes the data, while the data constrains event generation. If so, then how do we represent this unity of quite different things? What comes immediately to mind is an object-oriented database. "Objects" have both a state and a behavior. In terms of a programming language, the former is called a "field" and the latter a "method". We could combine an object-oriented language such as Java with a way to store data, such as XML. Being embarrassed by this amateur speculation in such august company, let me instead turn it into a question. There's a lot of discussion of XML in genealogy, but my impression it is presumed to be a flat file as a potential substitute for GEDCOM. However, are object-oriented databases or languages at all used or even discussed in genealogy? -- Haines Brown, KB1GRM

Haines Brown wrote: > > If so, then how do we represent this unity of quite different things? > What comes immediately to mind is an object-oriented database. It's also what comes to my mind. Take an apparently simple concept such as a name. Name structures are culturally determined. No single data structure will be able to satisfy everyone. In an OO environment, however, we could have an abstract name class with a sub-class for each cultural naming structure we have to deal with. -- Ian Hotmail is for spammers. Real mail address is igoddard at nildram co uk