If it's for a "linking table", you'd just have something like this:
CREATE TABLE linking_table (
first_id INTEGER,
second_id INTEGER,
PRIMARY KEY (first_id, second_id)
);
For an n-m relationship, that's the only way to do it.
Dean Harding.
P.S. The syntax may be wrong, that's just off the top of my head, but
you get the idea - a primary key doesn't have to be on one field only,
it can be on as many as you need.
> -----Original Message-----
> From: Desmond Lee [mailto:[EMAIL PROTECTED]]
> Sent: Sunday, 28 July 2002 12:27 pm
> To: [EMAIL PROTECTED]
> Subject: help me out here guys... you gotta have a primary key
>
> k....
>
> This is seems ridiculous to me,.. but i'll let you tell me if i'm just
> being
> stubborn.
>
> So, one of my associates has made a linking table (some people also
call
> it
> intersection table, cross tab table, but i believe that the propper
way to
> model a many to many relationship is via a "linking table"). in the
> linking
> table, there is no primary key defined. I believe that every table
must
> have
> a primary key. It is absolutely essential, otherwise you'll get tons
of
> problems including redundancy, and inconsistency. However, my
associate
> believes that our coding will ensure that such problems will be
avoided
> and
> that it's okay for a table to have no primary key defined. I totally
> disagree. Even if our code is perfect, a primary key must be defined.
>
> So, am i correct in being concerned, or am i just being close minded?
> If, i'm totally wrong, in what situations is it a good idea, okay, or
> benificial to not have a primary key defined for a table?
>
>
> Thanks
>
> Desmond
>
>
> (sql)
>
>
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