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Old February 26th, 2005, 08:58 PM
John Vinson
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On Sat, 26 Feb 2005 10:33:01 -0800, wattog
wrote:

I can't figure out whether I need a different table for each group, or
whether I can code records in a table for multiple categories. If I do use
different tables for each group, how do I connect the same person who appears
in several groups, so that I will make changes to only one record that will
be reflected across all instances of that record in other tables.


If you have a "many to many" relationship between Contacts and
Categories, the proper way to structure your tables is to have *three*
tables:

Contacts
ContactID Primary Key
FirstName
LastName
etc etc

Categories
Category Text Primary Key

ContactCategories
ContactID link to Contacts
Category link to Categories

Thus if a contact is in five categories, there would be five records
in ContactCategories for that contact; if you have 318 contacts in the
"Prospective Customer" category, there'd be 318 records in
ContactCategories, each with a different ContactID.

You could then create a Query joining Contacts to ContactCategories
with a criterion on Category to find all contacts in a particular
category.

John W. Vinson[MVP]