Maintain Addresses

All addresses for customers, employees, vendors, and contacts are stored in a single table.  A twelve character key, split equally into major/minor portions facilitates sharing a single address for multiple purposes.  Thus, if an entity has multiple relationships with an organization, only a single address need be maintained.  The major key of an address is the same as the customer id, vendor id, or employee id.  The minor key is used for maintaining multiple shipping, billing, and contact addresses for each customer or vendor.