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:
Mar. 24, 2009
Filed:
Jan. 19, 2005
Dilip Kumar Biswal, Union City, CA (US);
Isaac Kam-chak Cheng, San Jose, CA (US);
Cecilia O. Chu, El Dorado Hills, CA (US);
Donald Lee Clare, Morgan Hill, CA (US);
Louis S. W. Mau, Cupertino, CA (US);
Dilip Kumar Biswal, Union City, CA (US);
Isaac Kam-Chak Cheng, San Jose, CA (US);
Cecilia O. Chu, El Dorado Hills, CA (US);
Donald Lee Clare, Morgan Hill, CA (US);
Louis S. W. Mau, Cupertino, CA (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
A method and system for efficient snapshot querying include: providing a first version value for each data in a history table, where the first version value indicates a beginning of a period in which the data is valid; providing at least a second version value for each data in the history table, where the second version value indicates an end of the period in which the data is valid; receiving a request for a version of a database; and retrieving the data with the first version value less than or equal to the requested version and the second version value greater than or equal to the requested version. By maintaining a history table with redundant version information, the method and system are able to provide efficient snapshot querying while also avoiding the overhead burden of conventional approaches. No aggregates, joins, or sub-queries are required to retrieve a snapshot.