Intensional Query Processing in Object-Oriented Spatial Database Systems
Yang Hee Kim · The Journal of Korean Institute of Information Technology · 2009
When processing a query in a conventional database systems, a set of facts or objects (extensional answers) are usually returned as an answer. An intensional answer to a query is a set of characteristics of the extensional answers that satisfy the query. In this paper, by introducing rules for abstract expression in the object-oriented spatial databases and by applying the intensional query processing technique of deductive databases to object-oriented spatial databases, we make it possible not only to answer incomplete queries, but also to express the answer-set abstractly as the names of classes. Our approach consists of three phases: rule generation, pre-resolution and resolution. In the rule generation phase, we generate a set of rules based on an object-oriented spatial database schema and eliminate the recursion in rules. In the pre-resolution phase, rule transformation is done to get unique intensional literals. In the resolution phase, we use SLD-resolution to generate intensional answers.