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:
May. 03, 2005
Filed:
Jan. 08, 1998
Daniel Francis Lieuwen, Plainfield, NJ (US);
Akira Kawaguchi, New York, NY (US);
Inderpal Singh Mumick, Berkeley Heights, NJ (US);
Dallan Wendell Quass, Palo Alto, CA (US);
Kenneth A. Ross, New York, NY (US);
Daniel Francis Lieuwen, Plainfield, NJ (US);
Akira Kawaguchi, New York, NY (US);
Inderpal Singh Mumick, Berkeley Heights, NJ (US);
Dallan Wendell Quass, Palo Alto, CA (US);
Kenneth A. Ross, New York, NY (US);
Lucent Technologies Inc., Murray Hill, NJ (US);
Abstract
In a database, a database manager can generate a view, which, in concept, is a subset of the database, which is placed outside the database for use without disturbing the database, and without disturbance by others using the database. The subset, or view, can be understood as a collection of rows, or tuples, of data copied from the database. With views existing, multiple copies of data within the database now exist: the original in the database, and copies in the views. If one of these is changed, without corresponding changes made in the others, then inconsistencies occur, which cannot be tolerated. Under the invention, when a user seeks a lock on a view, indicating that a change may be imminent, the invention locks a superset of the tuples in the database from which the view is derived. A superset is a set which contains the set of tuples of the view, plus possibly others. Thus, more tuples are locked than strictly necessary. The excess locking is tolerated because other benefits are obtained.