Join Index Hierarchies for Supporting Efficient Navigations in Object-Oriented Databases
نویسندگان
چکیده
A join index hierarchy method is proposed to handle the “goto’s on disk” problem in objectoriented query processing. The method constructs a hierarchy of join indices and transforms a sequence of pointer chasing operations into a simple search in an appropriate join index file, and thus accelerates navigation in object-oriented databases. The method extends the join index structure studied in relational and spatial databases, supports both forward and backward navigations among objects and classes, and localizes update propagations in the hierarchy. Our performance study shows that partial join index hierarchy outperforms several other indexing mechanisms in object-oriented query processing.
منابع مشابه
Join Index Hierarchy: An Indexing Structure for Efficient Navigation in Object-Oriented Databases
A novel indexing structure, join index hierarchy, is proposed to handle the \goto's on disk" problem in object-oriented query processing. The method constructs a hierarchy of join indices and transforms a sequence of pointer chasing operations into a simple search in an appropriate join index le, and thus accelerates navigation in object-oriented databases. The method extends the join index str...
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A novel indexing structure, join index hierarchy, is proposed to handle the \goto's on disk" problem in object-oriented query processing. The method constructs a hierarchy of join indices and transforms a sequence of pointer chasing operations into a simple search in an appropriate join index le, and thus accelerates navigation in object-oriented databases. The method extends the join index str...
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