Pruning disk blocks of a clustered table in a relational database management system
US8996544B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 28, 2012 |
| Grant date | Mar 31, 2015 |
| Priority date | — |
| Expiry date | Feb 26, 2033 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F16/285
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
Techniques are provided for generating a “dimensional zonemap” that allows a database server to avoid scanning disk blocks of a fact table based on filter predicates in a query that qualify one or more dimension tables. The zonemap divides the fact table into sets of contiguous disk blocks referred to as “zones”. For each zone, a minimum value and a maximum value for each of one or more “zoned” columns of the dimension tables is determined and maintained in the zonemap. For a query that contains a filter predicate on a zoned column, the predicate value can be compared to the minimum value and maximum value maintained for a zone for that zoned column to determine whether a scan of the disk blocks of the zone can be skipped.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.