Sorting improves word-aligned bitmap indexes
نویسندگان
چکیده
منابع مشابه
Sorting improves word-aligned bitmap indexes
Bitmap indexes must be compressed to reduce input/output costs and minimize CPU usage. To accelerate logical operations (AND, OR, XOR) over bitmaps, we use techniques based on run-length encoding (RLE), such as Word-Aligned Hybrid (WAH) compression. These techniques are sensitive to the order of the rows: a simple lexicographical sort can divide the index size by 9 and make indexes several time...
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ژورنال
عنوان ژورنال: Data & Knowledge Engineering
سال: 2010
ISSN: 0169-023X
DOI: 10.1016/j.datak.2009.08.006