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" ?


---------------------------(end of broadcast)---------------------------
TIP 2: you can get off all lists at once with the unregister command
(send "unregister YourEmailAddressHere" to majordomo (AT) postgresql (DOT) org)

Hi Russel

On Jan 25, 2004, at 12:46 PM, Russell Shaw wrote:
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?

Michael Glaesemann
grzm myrealbox com


---------------------------(end of broadcast)---------------------------
TIP 9: the planner will ignore your desire to choose an index scan if your
joining column's datatypes do not match

Michael Glaesemann wrote:
Hi,

Maybe so. I thought of this and was wondering if it was the common solution.
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 suppliers?


---------------------------(end of broadcast)---------------------------
TIP 5: Have you checked our extensive FAQ?

http://www.postgresql.org/docs/faqs/FAQ.html

On Jan 25, 2004, at 2:23 PM, Russell Shaw wrote:

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

Michael Glaesemann
grzm myrealbox com


---------------------------(end of broadcast)---------------------------
TIP 6: Have you searched our list archives?

http://archives.postgresql.org