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:
Jan. 31, 2006
Filed:
Dec. 26, 2002
Peter Jay Haas, San Jose, CA (US);
Guy Maring Lohman, San Jose, CA (US);
Mir Hamid Pirahesh, San Jose, CA (US);
David Everett Simmen, San Jose, CA (US);
Ashutosh Vir Vikram Singh, San Jose, CA (US);
Michael Jeffrey Winer, Markham, CA;
Markos Zaharioudakis, Paris, FR;
Peter Jay Haas, San Jose, CA (US);
Guy Maring Lohman, San Jose, CA (US);
Mir Hamid Pirahesh, San Jose, CA (US);
David Everett Simmen, San Jose, CA (US);
Ashutosh Vir Vikram Singh, San Jose, CA (US);
Michael Jeffrey Winer, Markham, CA;
Markos Zaharioudakis, Paris, FR;
International Business Machines Corporation, Armonk, NY (US);
Abstract
A system, method and computer readable medium for sampling data from a relational database are disclosed, where an information processing system chooses rows from a table in a relational database for sampling, wherein data values are arranged into rows, rows are arranged into pages, and pages are arranged into tables. Pages are chosen for sampling according to a probability P and rows in a selected page are chosen for sampling according to a probability R, so that the overall probability of choosing a row for sampling is Q=PR. The probabilities P and R are based on the desired precision of estimates computed from a sample, as well as processing speed. The probabilities P and R are further based on either catalog statistics of the relational database or a pilot sample of rows from the relational database.