Estimating the number of distinct values for an attribute in a relational database table
US5999928A · kind A · utility
10Cited by
9References
23Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Jun 30, 1997 |
| Grant date | Dec 7, 1999 |
| Priority date | — |
| Expiry date | Jun 30, 2017 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S707/99936
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A method and apparatus for estimating the number of distinct values in a database table selects one of several numerical methods to solve a model of the number of distinct values in a database table based on a table size, a sample size, and the number of distinct values in the sample. The sample may be a sample previously collected for purposes other than to estimate the number of distinct values, and the number of records in the sample and the number of distinct values in the sample may be determined at the time the sample was collected.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.