Method and apparatus for optimizing access path in database
US9063973B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 20, 2012 |
| Grant date | Jun 23, 2015 |
| Priority date | — |
| Expiry date | Jul 3, 2033 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F16/24542
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
Apparatuses and methods for optimizing access path are provided. Execution of a query statement is sampled to obtain the information about a plurality of executing instances, the information about each executing instance comprises the literal value of the query statement in the instance and the filter factor corresponding to the literal value. The plurality of instances are grouped into a plurality of groups based on the filter factors corresponding to the literal values. The average filter factor of each group and the occurrence frequency of the group are obtained. The candidate access path created for the average filter factor of each group is accordingly obtained, and by taking the occurrence frequencies as weights, the weighted execution cost of each candidate access path is calculated for each group. The candidate access path with the minimum sum of the weighted execution costs for all groups is determined as the optimal access path.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.