Defining relationships...

O

Ozzone

I want to make sure im defining my relationships correctly, because it
appears that i have what im calling circular definitions(because of the way
the lines go in the Relationship Layout window), and im not sure if it is
acceptaple for good design.

Tables involved:
tblCustomers - CustId primary key
tblSiteData - SiteID primary key
tblProposals - PropID primary key
tblContacts - ContactID primary key

Each Customer can have many sites:
tblCustomers - tblSiteData -- CustID foriegn key - one-to-many

Each Customer can have many Proposals:
tblCustomers - tblProposals -- CustID foriegn key - one-to-many

Only one site per Proposal:
tblSiteData - tblProposals -- SiteID foriegn key - one-to-many

So far so good? If i arrange the 3 tables in the layout window, i have them
connected in a circle. Is that ok?

tblContacts holds all the additional contacts for a customer(the billing
contact is the Customer, additional contacts are salespersons and supervisors
employed by Customer).

Each Customer can have many additional Contacts:
tblCustomers - tblContacts -- CustID foriegn key - one-to-many

I want to be able to assign a Customer Salesperson Contact and a Customer
Supervisor Contact to each Site.

Each Contact can be responsible for many sites:
tblContacts - tblSiteData -- ContactId foriegn key - one-to-many

Then I assign a Site to a Proposal. I know the ContactID's can now be
brought into the Proposal, but do i have to define a realtionship between
tblProposals and tblContacts to be able to reference the Contacts
information?

Seems like i have too many relationships defined already. I have lines
crossing in the layout window and every example ive looked at was very clean,
no circles, no crossing lines.

I know i'm making this more complicated than it is so any and all feedback
appreciated :)
 
D

Douglas J. Steele

If it makes sense to your business rules to have that many relationships,
don't worry whether the lines cross in the drawing.
 

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