Method for maintaining an index
US5765168A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Aug 9, 1996 |
| Grant date | Jun 9, 1998 |
| Priority date | — |
| Expiry date | Aug 9, 2016 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F16/319
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A computer implemented method maintains an index of a database. The database stores information as a plurality of records. Batches of records are indexed by storing index entries in a memory. Each index entry includes a word entry for each unique portion of information of the database, and one or more location entries pointing at occurrences of the portions of information. The index entries are organized according to a collating order of the word entries. The location entries are stored sequentially for each word entry. The index entries are organized into a plurality of tiers of files. There is one tier of files for each batch of records indexed. A merged tier of files is periodically produced by merging a subsequently produced tier of files with a previously produced tier of files. The index entries of the merged tier of files are a logical union of the index entries of the subsequently and previous produced tiers of files. The location entries of deleted records are expunged while merging the tiers of files.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.