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Home -> Community -> Usenet -> c.d.o.server -> Re: Many to Many Relationship with a Twist
Van
Your following relation is unclear:
" Any NEWS item can be associated with C and/or R and/or B".
If you mean to say " Any NEWS item can be associated with 0 or 1 rows in C and/or R and/or B" then you don't have a many to many relationship and you don't need an intersection table.
However, if you mean to say " Any NEWS item can be associated with 0, 1, or
more rows in C and/or R and/or B" then you do have a many to many
relationship between NEWS and the other tables. If this is the case, I
would probably go the intersection route instead of trying to develop a more
"elegant" solution. "Elegant" in my experience means more complicated and
fraught with gotchas down the road that aren't immediately obvious. Give
the developers a break and don't make their jobs any more complicated then
it needs to be.
(just my opinion)
HTH
-- Jim Gregory Principal Consultant for Keane, Inc. Currently assigned to NCR "Opinions are my own and do not reflect those of Keane or my clients" Van Messner <vmessnerNOvmSPAM_at_discovernet.com.invalid> wrote in message news:16160e7a.9245beac_at_usw-ex0106-046.remarq.com...Received on Fri Jul 21 2000 - 00:00:00 CDT
>
> Imagine three tables C, R and B. C has a primary key of CKEY, R
> is RKEY and B is BKEY.
>
> Another table NEWS has a primary key of NEWSKEY.
>
> C, R and B can all be associated with zero to many NEWS items.
> Any NEWS item can be associated with C and/or R and/or B.
>
> One model is to put an intersection table between NEWS and C,
> NEWS and B, and NEWS and R.
>
> But when I add more tables at the level of C, R and B then I will
> need more intersection tables. Is there a more elegant solution?
> Please be specific about which would be the key and foreign key
> columns of any alternative solution.
>
> Many thanks,
>
> Van
>
>
>
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