Incremental view maintenance in object-oriented databases

• Authors: Reda Alhajj;Faruk Polat
• Venue: ACM SIGMIS Database
• Year: 1998

A database management system should support views to facilitate filtering of information in order to have only necessary and required information available to users with minimal delay. Although a lot of research efforts concentrated on views within the conventional relational model, much more effort is required when object-oriented models are considered. However, supporting views is only a step forward in achieving the purpose that requires improving the performance of the system by considering incremental maintenance of views instead of recomputing a view from scratch each time it is accessedIn this paper, we introduce a model that facilitates incremental maintenance of single-class-based object-oriented views by employing the deferred update mode that has proved to be more suitable for object-oriented databases in general. For that purpose, we categorize classes into base and brother classes corresponding to classes originally present in the database and those introduced as views, respectively. To each class, we add a modification list that keeps related modifications during different intervals. An interval starts with the creation or update of a view and ends with the creation or update of another view. A modification list is empty as long as no views depend on its class. Further, we introduce some algorithms that locate modifications done on related classes while trying to compute a given view incrementally. Finally, we give a theoretical justification showing that, in general, the introduced algorithms perform much better than doing computation from scratch each time a view is accessed.