The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 01, 2009
Filed:
Aug. 17, 2007
Paul H. Gusciora, San Rafeal, CA (US);
Paul H. Gusciora, San Rafeal, CA (US);
OSIsoft, Inc., San Leandro, CA (US);
Abstract
In a method for distributed database replication, local change records describing the local changes to the database at a node are transmitted to other nodes. Each node receives from the other nodes other change records describing changes to the database at the other nodes, and a log of change records is accumulated. Each change record describes a change made to a row at a source node, e.g., using data such as an identifier of the source node, a source node abstract clock value, a row identifier, and cell values of the row before and after the change. Autonomously from the other nodes, each node applies the other change records to its local copy of the database, considering the other change records in source node abstract clock order. The other change records are applied by checking for a collision between the other change records and the database and, when a collision is detected, selecting a persistent result by sequentially scanning through the log of change records in order of local abstract clock value to identify the persistent result.