Optimizing access plan for queries with a nested loop join
US11036736B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 22, 2017 |
| Grant date | Jun 15, 2021 |
| Priority date | — |
| Expiry date | Oct 13, 2039 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F16/284
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A method, computing system and computer program product are provided. A nested loop join access plan for a query is executed and processed records of a most outer table of a nested loop join that satisfy local predicates are counted. When a count of the processed records is not less than a threshold value, a cost to complete execution of the nested loop join access plan and a cost of executing a new access plan based on recalculated filter factors for local predicates of the query are compared. When the cost to complete is less, execution of the nested loop join access plan is resumed to complete running of the query. When the cost of executing the new access plan is less, the new access plan is executed to rerun the query. A result of the query is provided.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.