Abstract
QC-Trees is one of the most storage-efficient structures for data cubes in a MOLAP system. Although QC-Trees can achieve a high compression ratio, it is still a fully materialized data cube. In this paper, we present an improved structure PMC, which allow us to partially materialize cells in a QC-Trees. There is a sharp contrast between our partially materialization algorithm and other extensively studied materialized view selection algorithms. If a view is selected in a traditional algorithm, then all cells in this selected view are to be materialized. Our algorithm, however, selects and materializes data by cells. Experiments results show that PMC can further reduce storage space occupied by the data cube, and can shorten the time for update the cube. Along with further reduced space and update cost, our algorithm can ensure a stable query performance.
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
Preview
Unable to display preview. Download preview PDF.
References
Beyer, K., Ramakrishnan, R.: Bottom-up computation of sparse and iceberg cubes. In: Proc, SIGMOD, pp. 359–370 (1999)
Gray, J., Bosworth, A., Layman, A., Pirahesh, H.: Data cube: A relational aggregation operator generalizing group-by, cross-tab, and sub-totals. In: Proc, ICDE, pp. 152–159 (1996)
Hahn, C., et al.: Edited synoptic cloud reports from ships and land stations over the globe, 1982-1991. cdiac.est.ornl.gov/ftp/ndp026b/SEP85L.Z (1994)
Lakshmanan, L.V.S., Pei, J., Han, J.: Quotient Cube: How to Summarize the Semantics of a Data Cube. In: Proc. VLDB, pp. 778–789 (2002)
Lakshmanan, L.V.S., Pei, J., Zhao, Y.: QC-Trees: An Efficient Summary Structure for Semantic OLAP. In: Proc. SIGMOD, pp. 64–75 (2003)
Li, J., Li, Y., Srivastava, J.: Efficient Aggregation Algorithms on Very Large Compressed Data Warehouses. J. Comput. Sci. Technol. 15(3), 213–229 (2000)
Shanmugasundaram, J., Fayyad, U., Bradley, P.: Compressed data cubes for olap aggregate query approximation on continuous dimensions. In: Proc. SIGKDD, pp. 223–232 (1999)
Sismanis, Y., Deligiannakis, A., Roussopoulos, N., Kotidis, Y.: Dwarf: shrinking the PetaCube. In: Proc. SIGMOD, pp. 464–475 (2002)
Wang, W., Lu, H., Feng, J., Yu, J.: Condensed Cube: An Effective Approach to Reducing Data Cube Size. In: Proc. ICDE, pp. 155–165 (2002)
Zhao, Y., DeshPande, P., Naughton, J.: An Array-Based Algorithm for Simultaneous Multidimensional Aggregates. In: Proc. SIGMOD, pp. 159–170 (1997)
Author information
Authors and Affiliations
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 2005 Springer-Verlag Berlin Heidelberg
About this paper
Cite this paper
Li, H., Huang, H., Liu, S. (2005). PMC: Select Materialized Cells in Data Cubes. In: Tjoa, A.M., Trujillo, J. (eds) Data Warehousing and Knowledge Discovery. DaWaK 2005. Lecture Notes in Computer Science, vol 3589. Springer, Berlin, Heidelberg. https://doi.org/10.1007/11546849_17
Download citation
DOI: https://doi.org/10.1007/11546849_17
Publisher Name: Springer, Berlin, Heidelberg
Print ISBN: 978-3-540-28558-8
Online ISBN: 978-3-540-31732-6
eBook Packages: Computer ScienceComputer Science (R0)