Database system having logical row identifiers
US6546394B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 28, 1999 |
| Grant date | Apr 8, 2003 |
| Priority date | — |
| Expiry date | Dec 28, 2019 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F16/2228
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A database system having logical row identifiers (rowids) includes a secondary index which is traversed to locate a secondary index entry that includes a target secondary key value. Each secondary index entry also includes a logical rowid element. Each logical rowid element has both a primary key value element, and a datablock address element identifying a leaf block in an index-organized table that likely includes a row corresponding to the primary key value element. The leaf block is scanned to locate the row in the index-organized table that includes the target secondary key value and corresponds with the located, secondary index entry. A primary key scan is performed on the index-organized table if the row in the index-organized table is not located in the identified datablock.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.