Optimizing execution plans for in-memory-aware joins
US10025822B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 22, 2015 |
| Grant date | Jul 17, 2018 |
| Priority date | — |
| Expiry date | Aug 8, 2036 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F2212/401
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
Techniques are described herein for accurately estimating the cost of performing a join against “mirror format” data that is at least partially located in volatile memory. Mirror format data is a copy of on-disk data (a.k.a. persistent format data) stored in a different format in volatile memory. In the preferred embodiment described herein, the mirror format data is stored in a column-major format, while the persistent format data is stored in a row-major format. The cost of performing a join query with a particular join method against mirror format data is different than the cost of performing the same particular join method against persistent format data. Techniques described herein for estimating the cost of multiple join query execution plans, and selecting the most optimized plan.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.