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. 18, 1998
Filed:
Oct. 05, 1995
Philip L Boyer, San Jose, CA (US);
Gerald G Kiernan, San Jose, CA (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
A system, method, and program enables database management systems for relational and object-oriented databases to recognize a quantifier in a query as being designated as optional. An optional quantifier will participate in a query depending upon certain conditions. If the columns (or objects) projected out in the view that are dependent upon the quantifier are not used by the query, the quantifier is dropped from the definition of the view. The query is processed using only the relations in the view not associated with the optional quantifier. The results returned are as if a left outer join operation with duplicate elimination had been performed, although the actual processing of the query was independent of, i.e., did not involve, a left outer join operation. If the columns (or objects) projected out in the view that are dependent upon the quantifier are used by the query, the optional quantifier remains in the definition of the view and the query is processed using a join operation.