Extending ROCK & ROLL with Spatial Data Types : Part 1

The ROCK & ROLL deductive object-oriented database system has been used to develop applications that involve the querying and manipulation of spatial data. The approach to the development of these applications has hitherto required that a suitable set of spatial data types is deened and handed over to applications as a class library for reuse. While this approach is functionally adequate, it leaves open the way to potential inconsistencies in the treatment of geometries and to computational ineeciency, especially due to the absence of built-in spatial-indexing facilities and spatial-query optimization. Part 1 of this paper describes the embedding of a spatial algebra into the imperative language of ROCK & ROLL. This provides users with geometrically consistent, computationally eecient built-in support for spatial data types and operations, thereby lessening the burden associated with the development of complete spatial data handling applications in ROCK & ROLL. In Part 2, the same spatial algebra is embedded into the declarative, deductive language of ROCK & ROLL, thus allowing users to beneet from a deductive, declarative mode of expression in addition to built-in support for spatial query optimization.