Conference Paper

Relative prefix sums: an efficient approach for querying dynamic OLAP data cubes

Dept. of Comput. Sci., California Univ., Santa Barbara, CA
DOI: 10.1109/ICDE.1999.754948 Conference: Data Engineering, 1999. Proceedings., 15th International Conference on
Source: DBLP

ABSTRACT Range sum queries on data cubes are a powerful tool for analysis.
A range sum query applies an aggregation operation (e.g., SUM) over all
selected cells in a data cube, where the selection is specified by
providing ranges of values for numeric dimensions. Many application
domains require that information provided by analysis tools be current
or “near-current.” Existing techniques for range sum queries
on data cubes, however, can incur update costs on the order of the size
of the data cube. Since the size of a data cube is exponential in the
number of its dimensions, rebuilding the entire data cube can be very
costly. We present an approach that achieves constant time range sum
queries while constraining update costs. Our method reduces the overall
complexity of the range sum problem

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    ABSTRACT: Data warehouses contain data consolidated from several operational databases and provide the historical, and summarized data. On-Line Analytical Processing (OLAP) is designed to provide aggregate information to analyze the contents of data warehouses. An increasingly popular data model for OLAP applications is the multidimensional database, also known as data cube. A range sum query applies a sum aggregation operation over all selected cells of an OLAP data cube where the selection is specified by providing ranges of values for numeric dimensions. It is very useful in finding trends and in discovering relationships between attributes in the database. For today's applications, interactive data analysis applications which provide the current information will require fast response time and have reasonable update time. Since the size of a data cube is exponential in the number of its dimensions, it costs a lot of time to rebuild the entire data cube. To solve these updating problem, we present the recursive relative prefix sum method, which provides a compromise between query and update cost. From our performance study, we show that the update cost of our method is always less than that of the prefix sum method. Our recursive relative prefix sum method has a reasonable response time for ad hoc range queries on the data cube, while at the same time, greatly reduces the update cost.

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