Query transformation for union all view join queries using join predicates for pruning and distribution
US7188098B2 · kind B2 · utility
13Cited by
13References
30Claims
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Key dates
| Filing date | Sep 24, 2003 |
| Grant date | Mar 6, 2007 |
| Priority date | — |
| Expiry date | Jan 21, 2025 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S707/99943
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A method, apparatus, and article of manufacture for optimizing a query in a computer system, wherein the query is performed by the computer system to retrieve data from a database stored on the computer system. The optimization includes: (a) combining join predicates from a query with local predicates from each branch of one or more UNION ALL views referenced by the query; (b) analyzing the combined predicates; and (c) not generating the join when the analysis step indicates that the combined predicates lead to an empty result.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.