Re: Determin relationship

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Frank

I start with the data, not with the tables.

If I have, for example, an Order Fulfillment application, I have Orders,
Customers, Products and "Items Ordered".

But that still doesn't tell me quite enough about the underlying business
rules that apply. Can I have more than one customer on an order, or is my
"rule" one Order, one Customer (I'll go with this latter rule).

So which is the 'parent' (the "ONE") and which is the 'child' (the "MANY")?

I'm hoping for repeat business, so my assumption is that one Customer can
have many Orders (e.g., one-to-many). The primary key I use for Customer
will have to show up as a foreign key value in Order.

I'm hoping to sell a lot, so each Order can have many corresponding "Item
Ordered" records (again, one-to-many). The primary key in Order needs to
show as foreign key in "Item Ordered".

I'm using "Item Ordered" to show one Product per "Item Ordered" record ...
but I hope to sell many of the same Product, so one Product can show up in
many "Item Ordered" records (one-to-many). The same primary/foreign key
relationship exists.

Does that help?

--
Regards

Jeff Boyce
www.InformationFutures.net

Microsoft Office/Access MVP
http://mvp.support.microsoft.com/

Microsoft IT Academy Program Mentor
http://microsoftitacademy.com/

"Frank Situmorang" <hfsitumo2001@xxxxxxxxx> wrote in message
news:B6B45A79-B9EF-4839-8B43-4FB3E7C3F19E@xxxxxxxxxxxxxxxx
Hello:


Can anybody tell me the best website explaining the table relationship?
Coz
it is not so clear to me:

1. How can we determine whichone is to be the mother and which one is to
be
a child in the relation ship
2. Is it alwasy that One to Many relationship that One is Monther and many
is child?
4. Should the mother only use primary key as the linking fiels?

Thanks in advance for any idea provided.

Frank
--
H. Frank Situmorang

.

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