发明名称 |
Selectivity estimation for conjunctive predicates in the presence of partial knowledge about multivariate data distributions |
摘要 |
A method for consistent selectivity estimation based on the principle of maximum entropy (ME) is provided. The method efficiently exploits all available information and avoids the bias problem. In the absence of detailed knowledge, the ME approach reduces to standard uniformity and independence assumptions. The disclosed method, based on the principle of ME, is used to improve the optimizer's cardinality estimates by orders of magnitude, resulting in better plan quality and significantly reduced query execution times.
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申请公布号 |
US8135701(B2) |
申请公布日期 |
2012.03.13 |
申请号 |
US20080042065 |
申请日期 |
2008.03.04 |
申请人 |
KUTSCH MARCEL;MARKL VOLKER GERHARD;MEGIDDO NIMROD;TRAN TAM MINH DAI;INTERNATIONAL BUSINESS MACHINES CORPORATION |
发明人 |
KUTSCH MARCEL;MARKL VOLKER GERHARD;MEGIDDO NIMROD;TRAN TAM MINH DAI |
分类号 |
G06F7/00 |
主分类号 |
G06F7/00 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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