Automatically determining optimization frequencies of queries with parameter markers
US7987178B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 22, 2008 |
| Grant date | Jul 26, 2011 |
| Priority date | — |
| Expiry date | Jun 27, 2029 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F16/24542
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A method and system for automatically determining optimization frequencies of queries having one or more parameter markers. Execution plans for a query are generated and each plan is associated with one or more bind value sets. An optimization frequency is selected based on differences between pairs of execution costs where one execution cost of a pair is a cost of executing the query with a bind value set via a first execution plan and the other execution cost of the pair is a cost of optimally executing the query with the bind value set via a second execution plan. The differences are based on maximum selectivity or cardinality distances associated with the bind value sets. If none of the differences exceeds a predefined value, the query is optimized once. If at least one of the differences exceeds the predefined value, the query is reoptimized each time the query is executed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.