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:
Jun. 15, 2021
Filed:
Mar. 28, 2017
International Business Machines Corporation, Armonk, NY (US);
Thomas A. Beavin, Milpitas, CA (US);
Andrei F. Lurie, San Jose, CA (US);
Terence P. Purcell, Springfield, IL (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
Provided are techniques for efficient subquery predicate generation to reduce processing in a multi-table join. It is determined that a query is to be rewritten, wherein the query includes a predicate for a first column of a first table and a second column of a second table. The query is rewritten with generated subquery predicates for the first table that are to be applied to the second table and with generated subquery predicates for the second table that are to be applied to the first table. Minimum and maximum ranges for columns of the generated subquery predicates at a cursor open are determined. The minimum and maximum ranges are merged to determine inclusive ranges that exist in the first table and the second table. The generated subquery predicates are rewritten as derived local subquery predicates with the inclusive ranges. The query with the derived local subquery predicates is executed.