Bitmap segmentation
US6195656A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 13, 1999 |
| Grant date | Feb 27, 2001 |
| Priority date | — |
| Expiry date | May 13, 2019 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S707/99937
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A method and apparatus for segmenting bitmaps in a bitmap index is provided. A segmented bitmap includes a plurality of bitmap segments that are used to indicate which records in a body of records that is associated with the segmented bitmap satisfy a particular criteria. Each bitmap segment contains a string of bits that correspond to a corresponding range of records in the body of records. There may be gaps between the ranges represented by the bitmap segments when, for example, the body of records does not contain records in a particular range. For the purposes of retrieval, compression, de-compression, locking and logging, the database system treats each bitmap segment as a distinct data item.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.