Canonical abstraction for outerjoin optimization
US7478080B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 30, 2004 |
| Grant date | Jan 13, 2009 |
| Priority date | — |
| Expiry date | Jan 11, 2026 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S707/99935
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A system, apparatus, and program storage device implementing a method of optimizing queries used for searching a computerized database, wherein the method comprises providing a query comprising a sequence of inner joins and outerjoins; and rewriting the query by producing a sequence of outer Cartesian products for the query; producing a sequence of nullification operations on the query; and producing a sequence of best match operations on the query. The method further comprises optimizing the query using a query execution plan for processing the rewritten query, wherein the query execution plan expands a search space in the database for which the rewritten query may be run.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.