Logic-Based Semantic Query Optimization for Object Databases

John Grant, Jarek Gryz, Jack Minker, Louiqa Raschid

• DVI
• PS

Abstract

We present a technique for semantic query optimization (SQO) for object databases. We use the ODMG standard languages ODL and OQL. The object schema and object query are translated into a Datalog representation. Semantic knowledge about the object model and the particular application is expressed as integrity constraints. SQO is performed in the Datalog representation and an equivalent logic query, and subsequently an equivalent object query, is obtained. SQO is based on the residue technique of [CGM90]. We show that our technique generalizes previous research on SQO for object databases. It can also be applied to queries with methods and structure constructors and it can utilize access support relations.