Interrogation index file comparison
US5604901A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 3, 1995 |
| Grant date | Feb 18, 1997 |
| Priority date | — |
| Expiry date | Oct 3, 2015 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F7/02
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A method of comparing files takes three passes through data tables in memory to generate tables containing pointers to matches and mismatches by employing a method of keyword-index translation in which a keyword is taken from a first data table in a first pass and used as the index in loading an index table containing a pointer to the record containing that keyword. In a symmetric operation, a keyword is fetched from one table and used to interrogate the corresponding index table in a second pass. If there is a match, the record in the index table contains the pointer; and if there is a mismatch, the record contains a null. In an optional third pass, keywords are fetched from the other table and used to find records in the other table that are mismatches.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.