1. A data processing system for modifying a query during compilation of the query, the query comprising a request for an element of data from a table in a database and parameters identifying the requested element, the data processing system comprising: a query analysis mechanism for determining available information from parameters for locating a classification of the requested element and a classification associated with the query, the requested data classification controlling access to the requested element according to the query associated classification; a request mechanism for preparing a request to the external system, the request asking the external system to provide a suggested action for obtaining a comparison of the requested data classification and the query associated classification, the request comprising the available information; an external system interface for: requesting a suggested action from an external system for obtaining a comparison of the requested data classification and the query associated classification based on the available information, and receiving the suggested action from the external system responsive to the sent request; and a modification mechanism for incorporating the suggested action into the query to effect comparison of the requested data classification with the query associated classification.