Abstract: A reverse engineering technology is capable of automatically reversing from a physical data model comprising a relational or 4GL data model of an existing application database into a logical data model comprising classes and an entity-relationship (E-R) model of each class, the classes representing the different types of high-level objects that make up the application. This logical data model allows users to have a much clearer understanding of their application database thereby increasing their productivity and ease of maintenance of their existing applications. This is made possible by the method and structure of this invention first capturing the application semantics from the physical data model to provide a set of derived semantics. The derived semantics are then used to identify classes and derive the class definitions which are then used to derive the E-R model of each class.

Abstract: An end user query technology is taught which is capable of automatically understanding the database model and guiding the user to scout for the desired information, thereby increasing productivity and ease of information access. The user is freed from the need to understanding the database model, with the end user query facility of this invention quickly guiding the user to acquire the information. This is made possible by the end user query facility of this invention first recapturing the application semantics from the existing database model to provide a set of derived semantics. The derived semantics are then used by the end user query facility to intelligently guide the user to scout for the desired information in the database. In addition, the derived semantics can be easily updated by the end user query facility when the database model is changed.