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:
Dec. 21, 2004
Filed:
May. 24, 2001
Kuorong Chiang, Cerritos, CA (US);
NCR Corporation, Dayton, OH (US);
Abstract
A method, system and apparatus for performing an inclusion hash join and an exclusion hash join using a hash join are provided. The inner and outer tables are transposed to left and right tables, respectively. A hash table is created from the left table, the right table is scanned, and the hash table is probed. If the right table hash value matches a hash table value, the actual values are compared. If they match, the current outer table row is included in the result. If an exclusion condition is present, the hash table is probed with the right-table-row's hash value. If no hash values match, the outer table row is added to the result and the next row is addressed. If one or more hash values match, the actual values are compared.