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:
Aug. 02, 2005
Filed:
Jan. 10, 2002
Norifumi Nishikawa, Machida, JP;
Shigekazu Inohara, Tokyo, JP;
Koichi Shimazaki, Yokohama, JP;
Kiyomi Hirohata, Yokohama, JP;
Kohsaku Yamahira, Yokohama, JP;
Shigetoshi Hayashi, Fujisawa, JP;
Norifumi Nishikawa, Machida, JP;
Shigekazu Inohara, Tokyo, JP;
Koichi Shimazaki, Yokohama, JP;
Kiyomi Hirohata, Yokohama, JP;
Kohsaku Yamahira, Yokohama, JP;
Shigetoshi Hayashi, Fujisawa, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
The present invention relates to an optimization method in a database management system having the function of accessing external databases. Conventionally, whether functions contained in a query can be executed in external databases depends on a database management system having the functions, and therefore there has been a problem in that a database utilization method cannot apply to query optimization and query execution performance is reduced. To solve the above problem, a database management system having the function of accessing external databases is provided with an optimization step comprising the steps of: obtaining specification about whether to execute functions in a query in external databases; determining whether data referred to in a query is confined to one database; and determining whether a user specifies that the functions in the query are executed in external databases.