Multiparadigm query strategies in object-oriented geographic databases

The authors discuss three different paradigms suitable for querying object-oriented geographic databases. All together, the paradigms presented constitute the basis of a flexible and easy to use querying environment suitable for different categories of users. The first paradigm, to be adopted by programmer users, is based on the message sending mechanism of object-oriented database programming languages. The second paradigm is a browsing-based technique suitable for not unskilled users who have only a vague idea of the contents of the database. Finally, a frame-based approach is adopted for the third paradigm: this is suitable for non-programmer users who have a specific task to accomplish