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Why create a separate table just containing the primary keys of 2 separate tables?

Hi

I'm new to Access (2003) and i've just been given the horrible horrible task of trying to add extra functionality to an exisiting access database. I'm usually alright in the database front, since i've worked with mysql etc. But this relationship thing is really bugging the heck out of me.

First of all there's a few tables which contains primary keys from different tables (they are highlighted in bold) and then a relationship link to it from another table as a one to many. My first question is why do that and secondly; I'm trying to do the same thing (2 primary keys from another table) but its not allow me to have multiple keys.

Please help and many Thanks
Jun 12 '07 #1
2 1652
Please ignore my request. Someone in the office explained it to me.
Jun 12 '07 #2
NeoPa
32,556 Expert Mod 16PB
For the benefit of anyone else reading this thread the answer is as follows :

This is often used to link tables together in a Many-to-Many relationship.
Consider a family of people that own two cars. Individual members may drive 0, 1 or both of the cars. Each car may be driven by from 0 to all the members of the family. To express this relationship in an RDBMS it is usual to create a table of MemberCars which links to both the Cars table AND the Members table.
Jun 12 '07 #3

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