Classification-based method and apparatus for string selectivity estimation
US7395270B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 26, 2006 |
| Grant date | Jul 1, 2008 |
| Priority date | — |
| Expiry date | Mar 2, 2027 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S707/99942
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
Histogram construction and selectivity estimation for string and substring match queries in databases of data having strings associated with attributes. The histogram construction counts string-attribute pairs in the documents, and outputs string-attribute-count triples sorted by count. The collection is partitions the collection into buckets. A synopsis is generated for the partition, having an average selectivity or count of the string-attribute-count triples in the partition and summary information representing the set of string-attribute pairs belonging to the bucket. Subsequent queries, both for exact and substring matches, use the synopsis to estimate the selectivity of buckets.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.