Re: Heirarchical Data Structures. MS Access. Together?

"Jace Harker" <jharker_at_marlboro.edu> wrote in message news:vh9q26qvnd3dd9_at_corp.supernews.com...
> Hi, there, all. I have been working on this problem of heirarchical data
> structures for a while now. I'm trying to implement such a structure in
an
> MS Access environment, which seems to be pretty tricky. Although I have
> worked out a solution, it's rather complex and not very satisfying and I
was
> hoping there was some simple way that I'm missing. So I thought I would
ask
> and learn.
>
> (Please understand that although I'm an experienced programmer, this is my
> first foray into database programming. I've only worked with MS Access so
> far, although I'm happy to learn about other software!)
>
> So I'm looking for suggestions and ideas about:
>
> 1. General info about heirarchies in databases. Is there db software
> specifically designed for this kind of thing? From reading a few posts I
> know that there are different kinds of heirarchies for different purposes.
> 2. How to attack the heirarchy problem with Access. This is my current
> environment because of the requirements of the customer. How might I
> organize my tables and queries? How would I correspondingly design my
> forms?
> 3. What do you think I ought to know, or ask, that I'm not asking about?
>
> Some people may have a different idea than me as to what "heirarchical
data
> structure" means, so I thought I would give a general idea of my situation
> below so we're all on the same page.
>
> In my heirarchy, the data associated with a person or company (entity) is
> arranged in layers so that an entity can only possess data on a lower
level
> if they already have a corresponding data element at a higher level.
There
> can be no limit to the number (depth) of levels or the number of data
> entries on each level. (Think of this as a mailing list/info list where I
> need to store specific information about people and companies and their
> relationships with each other.) In addition, connections between entities
> also allow access to new data options.
>
> This is further complicated by the fact that data can be boolean or string
> or other, and that I must be able to filter by different data entries.
Most
> importantly, I want users to be able to add data entries to the heirarchy
as
> easily as one would add fields to a database (that's essentially what they
> are).
>
> For example:
>
> 1. Health Care Worker
> A. # of Patients per week
> B. Doctor?
> C. Nurse?
> D. Assistant?
> 2. NASA Employee
> A. Astronaut?
> B. Engineer?
> C. PR Expert?
> D. Amount of time spent in space
> 3. Boy Scouts
> A. Cub Scout?
> B. Boy Scout?
> C. Eagle?
> D. Den Mother?
> E. Age you started
>
> These might apply to a person. So the person could be either #1 or #2,
but
> not both at once, but the person could be #3 or not, regardless. If the
> person is #1 then she is able to select one of B,C, or D, and put a value
in
> for A. And so on. Of course the person would also possess a number of
> top-level fields like Name, Address, Phone, etc., but those by themselves
> would not be a problem.
>
> There are different KINDS of entity: People, and Companies. They can have
> relationships with each other (for example, Dr. John Smith, MD, is
> affiliated with Springfield General Hospital). Different kinds of entity
> get different options (Companies would not get the Health Care Worker
option
> ;-).
>
> Entity relationships unlock data options: "Dr. John Smith" is related to
> "Springfield General". Because Springfield General has been selected as
> type "Hospital", Dr. Smith's record _now_ allows us to choose his specific
> hospital staff title and watch hours from a list. But those options
> _would_not_ appear if he did not have a relationship with that particular
> type of company.
>
>
> That's the basic idea. I apologize for not knowing the proper
terminology,
> but I'm fairly new to database programming and this is my first experience
> with this particular problem.
>
> Thanks again for all input!
>
> Jace
>
>

http://www.mvps.org/access/

HTH
Larry Linden MVP

This posting is provided "AS IS" with
no warranties, and confers no rights. Received on Wed Jul 16 2003 - 16:14:03 CEST