Table relation

[TC]

I am hoping someone can shed some light on this. Say we
have 3 brands of computers, each brand has their own type,
and the customer may order 2 brands with 3 types of each
brand. How do I set up the relationship of this?

Computer
BrandID
Brand

BrandType
TypeID
Type

Customer
CustomerID
Name
Address

Thanks for any help.

 

[John Vinson]

I am hoping someone can shed some light on this. Say we
have 3 brands of computers, each brand has their own type,
and the customer may order 2 brands with 3 types of each
brand. How do I set up the relationship of this?

Computer
BrandID
Brand

BrandType
TypeID
Type

Customer
CustomerID
Name
Address

The customer isn't ordering a type - the customer is ordering an
object, a physical computer box. You need a Table to represent this
entity, with one record for each physical computer which a customer
can order. Also, since each BrandID can have multiple Types, you need
a foreign key - BrandID should be a (nonunique, indexed) field in the
BrandType table.

Finally, since each customer can buy multiple boxes, and each type of
box can be bought by several customers, you have a many to many
relationship which needs another table (let's call it Purchases).

Try:

Computer
BrandID
Brand

BrandType
TypeID
BrandID <link to Computer>
Type

Customer
CustomerID
Name
Address

Purchases
CustomerID <who bought something>
TypeID <what did they buy>
DateSold
<other information about this purchase>