Optimizer statistics and cost model for in-memory tables
US10073885B2 · kind B2 · utility
3Cited by
42References
24Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jul 22, 2015 |
| Grant date | Sep 11, 2018 |
| Priority date | — |
| Expiry date | Aug 21, 2036 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F2212/401
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
Techniques are provided for determining costs for alternative execution plans for a query, where at least a portion of the data items required by the query are in in-memory compression-units within volatile memory. The techniques involve maintaining in-memory statistics, such as statistics that indicate what fraction of a table is currently present in in-memory compression units, and the cost of decompressing in-memory compression units. Those statistics are used to determine, for example, the cost of a table scan that retrieves some or all of the necessary data items from the in-memory compression-units.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.