Improving estimation accuracy of aggregate queries on data cubes
نویسندگان
چکیده
منابع مشابه
Efficient Aggregate Queries on Data Cubes
As computers are developing rapidly and become more available to the modern information society, the possibility and ability to handle large data sets in database applications increases. The demand for efficient algorithmic solutions to process huge amounts of information increases as the data sets become larger. In this thesis, we study the efficient implementation of aggregate operations on t...
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Approximate range aggregate queries are one of the most frequent and useful kinds of queries for Decision Support Systems (DSS). Traditionally, sampling-based techniques have been proposed to tackle this problem. However, its effectiveness will degrade when the underlying data distribution is skewed. Another approach based on the outlier management can limit the effect of data skew but fails to...
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A range query applies an aggregation operation (e.g., SUM) over all selected cells of an OLAP data cube where the selection is speci®ed by providing ranges of values for numeric dimensions. Range sum queries on data cubes are a powerful analysis tool. Many application domains require that data cubes are updated often and the information provided by analysis tools are current or ``near current''...
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ژورنال
عنوان ژورنال: Data & Knowledge Engineering
سال: 2010
ISSN: 0169-023X
DOI: 10.1016/j.datak.2009.08.010