Re: Hierarchical Relationship
Date: 2000/03/03
Message-ID: <38bf0301.7784057_at_news.shuswap.net>#1/1
Bernard Peek <Bernard_at_shrdlu.com> wrote:
>In article <89liln$7h0$1_at_news1.xs4all.nl>, John Smith
><someone_at_microsoft.com> writes
>>Hi,
>>
>>I am trying to make a Familytree in Access.
>>In simplified form I have made
>>2 tables: TblPerson and TblParents
>>and 1 Querie: QryPerson&Parents.
>>
>>In TblPerson I have the basic properties of a person (ID, Name, sexe etc.).
>>In TblParents I have 3 fields: Person_ID, Father_ID and Mother_ID
>>
>>TblParents is linked 1-to-1 with TblPerson by [TblPerson].[ID] and
>>[TblParents].[Person_ID].
>>The other 2 fields (Father_ID and Mother_ID) are fields that look up their
>>values in TblPerson.
>>
>>QryPerson&Parents joins the 2 tables so that I get 1 recordset of a person
>>including who his parents are.
>>
>>So far so good but there is one problem. I'd like to build in some
>>validation. For example; one should not be able to select a distant
>>offspring or a distant ancestor as a parent.
>
>You can probably do enough validation by looking at the date of
>birth/death and making sure that nobody marries someone born more than a
>hundred years earlier.
That latter is not an absolute constraint.
>Other validation rules could get a little tricky, I do know someone
>whose family tree has a loop in it. It wasn't legal but it happened
>anyway.
How could a loop be possible? I think you mean something else: what?
Here's an unusual case for length of generations. It's from Stan McLean's "The History of the O'Keefe Ranch" (ISBN: 0-919873-08-1), p. 140:
Casey (b. 1970). It may be interesting to point out again that his paternal grandfather was born in 1837.
Sincerely,
Gene Wirchenko
Computerese Irregular Verb Conjugation:
I have preferences. You have biases. He/She has prejudices.Received on Fri Mar 03 2000 - 00:00:00 CET