1. A method for controlling access to personally identifiable information (PII) of a data owner in a database system, comprising: allowing the data owner to specify different opt-in or opt-out choices with respect to different business purposes for a given PII attribute, wherein the business purposes are listed in a privacy policy, which indicates an organization's control of PII in accordance with the data owner's preference, and wherein the data owner can opt out voluntary but not mandatory attributes information containing PII; receiving a request from an application to access attributes associated with the data owner in the database system; identifying a business purpose that the application has in making the request, wherein the business purpose identifies how the application uses the accessed attributes; identifying a set of attributes associated with the data owner corresponding to the identified business purpose; determining that the identified attributes contain a PII attribute that the data owner has opted out; and, enforcing access control by restricting access to the identified attributes containing the PII attribute based on the data owner's choice with respect to the PII attributes for the identified business purpose.