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:
Apr. 19, 2011
Filed:
Apr. 21, 2004
Fei GE, Palo Alto, CA (US);
Sivasankaran Chandrasekar, Palo Alto, CA (US);
Nipun Agarwal, Santa Clara, CA (US);
Ravi Murthy, Fremont, CA (US);
Eric Sedlar, San Francisco, CA (US);
Fei Ge, Palo Alto, CA (US);
Sivasankaran Chandrasekar, Palo Alto, CA (US);
Nipun Agarwal, Santa Clara, CA (US);
Ravi Murthy, Fremont, CA (US);
Eric Sedlar, San Francisco, CA (US);
Oracle International Corporation, Redwood Shores, CA (US);
Abstract
Cost-based optimizer functionality for an XML database repository provides means for optimizing the execution of database queries that access XML resources in the database repository. Statistics about XML resources that are stored in the database repository are gathered, stored and utilized by a query optimizer to compute computational costs associated with each of multiple methods of accessing particular XML resources requested in a database query. Hence, the optimizer is able to select the most efficient query execution plan based on the costs of possible access paths. In one embodiment, specific statistics about the hierarchical structure of XML resources stored in the XML database repository are gathered, stored in a relational table in the database management system, and used to compute the selectivity of query predicates and the index cost associated with traversing one or more indexes to access requested XML resources.