Lossless Reduction of Datacubes using Partitions

نویسندگان

  • Alain Casali
  • Sébastien Nedjar
  • Rosine Cicchetti
  • Lotfi Lakhal
  • Noel Novelli
چکیده

Datacubes are specially useful for answering efficiently queries on data warehouses. Nevertheless the amount of generated aggregated data is huge with respect to the initial data which is itself very large. Recent research has addressed the issue of a summary of Datacubes in order to reduce their size. The approach presented in this paper fits in a similar trend. We propose a concise representation, called Partition Cube, based on the concept of partition and we give a new algorithm to compute it. We propose a Relational Partition Cube, a novel ROLAP cubing solution for managing Partition Cubes using the relational technology. Analytical evaluation show that the storage space of Partition Cubes is smaller than Datacubes. In order to confirm analytical comparison, experiments are performed in order to compare our approach with Datacubes and with two of the best reduction methods, the Quotient Cube and the Closed Cube.

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عنوان ژورنال:
  • IJDWM

دوره 5  شماره 

صفحات  -

تاریخ انتشار 2009