Each provincial liquor control board has sales and product information in different formats. These different formats must be generalized to be able to derive any reporting out of it. The following approach is used to manage and process the inconsistent data:

1. Each province will have 2 data tables: sales and products
2. Each province has their own way of identifying products (UPC, article no, …)
3. Instead of using the province's identifier, the sales table will link to the product table using an internal numeric key. This is because a product can change but still have the same identifier. For example, if product #123 was produced in the UK but is now being produced in Canada, the producing country has changed but the product # is the same. We need a separate key to differential between these two instances.
4. Products that have been changes will have a start_date and an end_date that specifies within in which period the product information is valid.