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arXiv · 1612.04094

Efficient Representation of Multidimensional Data over Hierarchical Domains

Nieves R. Brisaboa·Ana Cerdeira-Pena·Narciso López-López·Gonzalo Navarro·Miguel R. Penabad·Fernando Silva-Coira
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Abstract

We consider the problem of representing multidimensional data where the domain of each dimension is organized hierarchically, and the queries require summary information at a different node in the hierarchy of each dimension. This is the typical case of OLAP databases. A basic approach is to represent each hierarchy as a one-dimensional line and recast the queries as multidimensional range queries. This approach can be implemented compactly by generalizing to more dimensions the $k^2$-treap, a compact representation of two-dimensional points that allows for efficient summarization queries along generic ranges. Instead, we propose a more flexible generalization, which instead of a generic quadtree-like partition of the space, follows the domain hierarchies across each dimension to organize the partitioning. The resulting structure is much more efficient than a generic multidimensional structure, since queries are resolved by aggregating much fewer nodes of the tree.

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Nieves R. Brisaboa, Ana Cerdeira-Pena, Narciso López-López, Gonzalo Navarro, Miguel R. Penabad, Fernando Silva-Coira. 2016-12-13. Efficient Representation of Multidimensional Data over Hierarchical Domains. https://doi.org/10.1007/978-3-319-46049-9_19

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