Branch Index
نویسندگان
چکیده
In this paper, we present an access method called branch index for query processing of the aggregation hierarchy as a tree in object-oriented databases. The algorithm of branch generation will be proposed to generate all branches for the tree aggregation of classes in the database. For each branch, the information of linking objects is stored so that class traversal methods can be eliminated. Using a set of attribute indexes and identity indexes for each branch, associative searching can be conveniently performed. We discuss the retrieval and update operation and then develop cost models in terms of storage overhead, retrieval cost and update cost. When compared with the path dictionary index for multiple paths, the result shows that our approach has less storage overhead and the retrieval cost is improving.
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