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:
Oct. 05, 1999
Filed:
Jun. 25, 1997
Applicant:
Inventors:
Josephine M Cheng, San Jose, CA (US);
Ting Yu Leung, San Jose, CA (US);
Mir Hamid Pirahesh, San Jose, CA (US);
Assignee:
International Business Machines Corporation, Armonk, NY (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G06F / ;
U.S. Cl.
CPC ...
707-2 ; 707-3 ; 707-4 ; 707-5 ; 707100 ; 707102 ; 707103 ;
Abstract
Method for specifying SQL 'full outer joins' which enables the use of arbitrary join conditions in specifying the query. This is enabled by equating a full outer join with a left outer join unioned with a right outer join less the matched tuples from the right outer join. A number of embodiments further present improvements in execution speed. One such improvement utilizes as a second operand of the union query a novel operator, the 'ANTI-JOIN'. The anti-join is implemented as a right outer join coupled with an ISNULL predicate.