Generalisation log for managing and utilising a multi-representation spatial database in map production

This paper describes a data model for logging map generalisation process information to facilitate data authentication and update propagation in a multi-representation spatial database environment. Generalisation is modelled as a directed acyclic diagram of prioritised generalisation process instances, which is further divided into independent operations as the atomic functional unit for generalisation. Generalisation parameter values and the roles of features in operations are stored. The full generalisation history of each feature may be traced for data authentication and quality analysis, or for update propagation. This model also includes the design of a feature versioning mechanism. In addition, OSGenLog, a set of platform-independent APIs to create generalisation logs, has been implemented in Gothic object-oriented database management system.