Create mart model for products

For an e-commerce data warehouse, it's also common to build out a products data mart, on top of a customers data mart, to answer questions about the product.

A products data mart should have the following attributes:

1. Be unique on the product grain (e.g., one row per product).
2. Contains information on the product level such as product name, category.
3. Assist in answering critical business questions such as profit analysis for each product.

In this exercise, we will dig a bit deeper on how to get to that final goal of building out a profits data mart so that it is easy for the end user to do profit analysis.

As a reminder, profit is calculated by:

Profit = Sales Amount - Cost of Goods Sold