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. 17, 2000
Filed:
Jun. 25, 1998
Robert Joseph Bestgen, Dodge Center, MN (US);
Randy Lynn Egan, Rochester, MN (US);
Carol Ledermann Ramler, Rochester, MN (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
A method and computer program product are provided for processing subquery join composites using hash join in a computer system. A hash table is built for a first table to be joined with a second table. A cursor is built for the second table. For each tuple in the second table, the hash table for the first table is probed. If a match is found, then any non-equal join predicate is evaluated. A unique fanout join is processed to return an error if a tuple or row from the second table joins to more than one row in the first table where the result of the basic predicate subquery can only be one row. A distinct fanout join is processed when the tuple or row from the second table joins to a row in the first table, the row is returned, advancing to a next tuple in the second table without checking for any more matches on the first table.