The Ra*-tree: An improved R-tree with Materialized Data for Supporting Range Queries on OLAP-Data
نویسندگان
چکیده
OLAP applications make use of fast indexes and materialization of data. Most research treats just one topic. Either the materialized values or the design of index structures are considered. This paper examines a possible combination of both techniques. The R -tree is taken as an example of a multi-dimensional index structure. Aggregated data is stored in the inner nodes of the index structure in addition to the references to the successor-nodes. We describe how this mechanism works in detail and present results of performance evaluation.
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