Patent · US Active

Cost-based subquery correlation and decorrelation

US7840552B2 · kind B2 · utility

0Cited by

21References

16Claims

0Family size

Assignee

International Business Machines Corporation · US

Inventors

Thomas A. Beavin · Milpitas, US
Mengchu Cai · San Jose, US
Yao-Ching Chen · Saratoga, US
Hsiuying Cheng · Fremont, US
Fen-Ling Lin · San Jose, US
Irene Ching-Hua Liu · San Jose, US
Jerry Mukai · San Jose, US
Demai Ni · Davis, US
Yoichi Tsuji · Sagamihara, JP
Li Xia · Qingdao, CN
Ying Zeng · Fuzhou, CN

Key dates

Filing date	Apr 16, 2008
Grant date	Nov 23, 2010
Priority date	—
Expiry date	May 16, 2029

Classification

Technology area (CPC Y)Emerging Cross-Sectional Technologies
CPC primaryY10S707/99943
WIPO fieldComputer technology
WIPO sectorElectrical engineering

Abstract

Techniques are provided that determine that a query includes at least one subquery that may be correlated or decorrelated. An internal representation of the query that represents the subquery in both correlated and decorrelated form is generated, wherein the internal representation includes at least one virtual table.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.