Multiway associations

[Russell Shaw]

Hi,
I'm making my first database.

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" ?
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[Paul Thomas]

On 25/01/2004 05:06 Russell Shaw wrote:

Hi,
I'm making my first database.

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 way would be to have a separate vendorpart table something like

CREATE TABLE vendorpart
(
vendor_id int4,
part_id int4
);

which holds the relationships. You'll to define indexes, contraints and
foreign keys on it.
--
Paul Thomas
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