On Jan 25, 2004, at 2:23 PM, Russell Shaw wrote:
> Michael Glaesemann wrote:
>> Hi Russel
>> On Jan 25, 2004, at 12:46 PM, Russell Shaw wrote:
>>> I have a list of parts, each of which is sold by multiple
>>> vendors. I also have a list of vendors, each of which sell
>>> multiple parts.
>>> How should i arrange the tables for this that doesn't involve
>>> having lots of empty fields "just in case" ?
>> One common way to do this is to have three tables: one suppliers, one
>> parts, and one suppliers-parts referencing suppliers and parts.
>> Does that help?
> Maybe so. I thought of this and was wondering if it was the common
> Should it be something like:
> spid supplier part
> 0 sid_1 pid_1
> 1 sid_1 pid_2
> 2 sid_2 pid_2
> 3 sid_3 pid_3
> 4 sid_3 pid_1
> Ie, the third table just stores all the combinations of parts and
Yup. The spid might be superfluous, depending on what you need your
database for. I've never needed one. You're probably only going to be
doing queries like
SELECT part FROM suppliers_parts WHERE suppplier = sid_1
or variants of these. Probably will never touch the spid column.
(Unless of course you have a particular reason for doing so :)
grzm myrealbox com
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