I have been importing records of organizations and people that is aimed to creating a contacts database. I have several tables with different kind of contacts (such as churches, schools, businesses, etc.) Some of the contacts are actual people with out an organization attached to them, and some of the contacts are just the organization without contact names attached to them. Some have addresses, phone numbers, & emails. Some contacts have all or no addresses, phone numbers, or emails attached. I can't find any field to make the primary key so I can tie up the relationships between the tables. Should I create a "contact number" to identify, if so, how do I do that now that all of the records are already imported to the database.