How to design a car-packages-database?

Question

I have a logic-thinking problem. How should I design following database?

A manufacturer sells cars. He sells them as they are, or with a package A, or with a package B, or with both packages.

I would create a table with the different car models, then a table with the different packages, but I don't know how to create the mapping-table, which links the cars to the different packages and prices?

The problem is the packages don't have a price (just the cars and the cars with packages included).

Answer 1

Add "offer" table. This table will contain price. Each offer should have at least one car and no, one, two, many, or all (if there will be more then 2 of them) packages.

Answer 2

I would guess that a car would have a manufacturers suggested retail price (MSRP). Each package or option would have its own additional price on top of the MSRP.

I'd have a base Car table, a Package table, and another purchased Car table, one to many with a Customer table, where the Customer can associate their base Car with one or more Package instances.

Answer 3

If you want to do it correctly, you need to use Table Inheritance.

You sell abstract products. One type of product is a car. Another is a "combo" (aka "marketing package") which is composed of other products.

There are some good data modeling books that cover this.