Re: Newbie - restructuring to eliminate many-to-many

From: JRStern <JRStern_at_gte.net>
Date: Sat, 03 Mar 2001 00:12:08 GMT
Message-ID: <3aa035b2.28505158_at_news.gte.net>

On Fri, 02 Mar 2001 22:11:12 GMT, "in too deep" <fieury_at_hotmail.com> wrote:

>The only way I can see to build the database is with many-to-many
>relationships, but I fear that will make it much more difficult to code (in
>.asp).

This is like the simplest possible case of many-to-many. Just put an "association table" in between with plan and partner fields. There is nothing wrong with this, for gosh sakes, it's what relational databases are all about!

You then use "joins" in select statements to look up what you want.

Table PlanPartner
* plankey

partnerkey (the primary key for this table is plankey+partnerkey) (this is the "association table")

Table Partner
* partnerkey

partner description
address
contact
whatever

(Also maybe subject/teacher/whatever tables, of course)

select plan.*, partner.*
  from plan
    inner join planpartner
      on plan.plankey=planpartner.plankey     inner join partner
      on planpartner.partnerkey=partner.partnerkey   where plan.subject = 'science'

          or
        partner.partnerkey="GEDallas"

etc.

J. Received on Sat Mar 03 2001 - 01:12:08 CET

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