Re: Entity Relationship Modelling Problem for a Genealogy RDB

Thanks for the info James I'll check it out

Guy

"James" <jraustin1_at_hotmail.com> wrote in message news:a6e74506.0110281125.7b208d6d_at_posting.google.com...
> > INDIVIDUAL -> 1:N -> BIRTH <- N:1 <- LOCATION1 (civil)
> > INDIVIDUAL -> 1:N -> BAPTISMAL <- N:1 <- LOCATION2 (religious)
> > INDIVIDUAL -> 1:N -> DEATH <- N:1 <- LOCATION1
> > INDIVIDUAL -> 1:N -> FUNERAL <- N:1 <- LOCATION2
> > Each middle entity is a union of two foreign keys and a date.
> >
> > The entity MARIAGE:
> > 1st - depending on the structure it may require a unique identifier!
> > 2nd - 2 foreign keys mapped to INDIVIDUAL are needed to establish the
union.
> > 3rd - This blessed event may be certified by the state and/or sanctified
> > by the church. How do you establish the right relationship to the
> > proper location where the event(s) took place?
> > 4th - individuals have been known to get married, get divorced and get
> > married to each other again. Non-unique entries on foreign keys!
>
> One possible solution using an objected-oriented database is shown
> below:
>
> Person
> .Birth
> ->Date
> ->Loc
> .Baptism
> ->Date
> ->Loc
> .Marriage
> Marriage1
> ->Date
> ->Spouse
> ->Loc
> .Divorce
> ->Date
> MarriageN
> .Death
> ->Date
> ->Loc
> .Funeral
> ->Date
> ->Loc
>
> Note: "." is a property, "->" indicates a reference. Each instance can
> have fewer or more properties than described in its class. Each
> property can have multiple values as indicated by its children. Each
> property can have multiple sub properties. Each object has a unique
> id. It is possible to describe a person with multiple births,
> baptisms, marriages (monagomy, bigamy, polygamy), divorces, deaths and
> funerals. You'll need many tables for an equivalent normalized
> solution in RDB.
>
> XDb is an object-oriented database that can manage complex/variable
> data structures. Download your free copy from http://www.xdb1.com
Received on Mon Oct 29 2001 - 04:21:27 CET