Re: foreign vs primary key

mikeg wrote:
>
> I have read a number of texts regarding the terms foreign and primary keys
> but I just can't get a feel for their uses.
>
> any help appreciated,
>
> mike

Think of Parent-Child. The foreign key is a key in a table that is the primary key in another table.

E.G.

  Authors Table

     Author_ID, int, primary key
     First_name, char
     Last_name, char
     DOB, date

  Books Table

     ISBN, char, primary key
     Author_ID, int, foreign key (Authors Table)
     Title, char
     Date_published, date
     Category, char

Dan Received on Wed Sep 19 2001 - 23:12:17 CEST