Cost-based optimizer, and cost estimation method and device thereof
US11023466B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 22, 2018 |
| Grant date | Jun 1, 2021 |
| Priority date | — |
| Expiry date | Nov 22, 2038 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F17/18
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A cost based optimizer and a cost estimation method and device. The method includes: in response to deciding that acquired statistical information is incomplete, determining a corresponding cost estimation manner according to an operation type of an operation tree relying on the statistical information (S11); determining a cost estimate of the corresponding operation type based on the cost estimation manner (S12); and determining an accumulative cost estimate of the operation tree according to the cost estimate corresponding to the operation type relying on the statistical information and a cost estimate corresponding to an operation type not relying on the statistical information (S13). Therefore, cost estimation may be performed for a temporary table and a subquery created in a running process, and is not limited by a data scale in a scenario of massive data.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.