The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 20, 2008
Filed:
Jul. 28, 2005
Marcel Kutsch, Cologne, DE;
Volker Gerhard Markl, San Jose, CA (US);
Nimrod Megiddo, Palo Alto, CA (US);
Tam Minh Dai Tran, San Jose, CA (US);
Marcel Kutsch, Cologne, DE;
Volker Gerhard Markl, San Jose, CA (US);
Nimrod Megiddo, Palo Alto, CA (US);
Tam Minh Dai Tran, San Jose, CA (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
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.