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:
Jan. 04, 1994
Filed:
Jun. 25, 1991
David B Lomet, Westford, MA (US);
Betty J Salzberg, Newton, MA (US);
Digital Equipment Corporation, Maynard, MA (US);
Abstract
The present invention includes an approach to index tree structure changes which provides high concurrency while being usable with many recovery schemes and with many varieties of index trees. The present invention permits multiple concurrent structure changes. In addition, all update activity and structure change activity above the data level executes in short independent atomic actions which do not impede normal database activity. Only data node splitting executes in the context of a database transaction. This feature makes the approach usable with diverse recovery mechanisms, while only impacting concurrency in a modest way. Even this impact can be avoided by re-packaging the atomic actions, at the cost of requiring more from the recovery system.