Patent · US Expired

System for modifying a database using a transaction log

US6418455B1 · kind B1 · utility

2Cited by
19References
9Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 17, 2000
Grant dateJul 9, 2002
Priority date
Expiry dateOct 17, 2020

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S707/99953
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

The present invention is a computer system for modifying a database which comprises a computer that modifies records stored in a database. In the process for modifying records in the database, addresses to memory locations in a disk storage unit are accessed during the commit phase by first checking the address space in a transaction log. The computer system of the present invention operates by committing transactions without locking out readers. This is possible because any changed data in the database is reflected in the transaction log and the log must be accessed prior to reading from the disk storage unit. As a result, the user sees changed data when the log is accessed, or if data has not been changed, the log merely directs the computer to the address in the original database storage where unchanged data is stored.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.