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:
Feb. 15, 1994
Filed:
Jul. 11, 1991
Applicant:
Inventor:
David B Lomet, Westford, MA (US);
Assignee:
Digital Equipment Corporation, Maynard, MA (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G06F / ;
U.S. Cl.
CPC ...
395600 ; 395425 ; 3642821 ; 3642814 ; 364974 ; 364D / ;
Abstract
When a subtransaction (46) of a higher-level transaction (50) commits during the operation of a database (10), the database enters into its operation log a record (FIG. 6 ) that acts both as a commit record for the subtransaction (46) and as an update record for the higher-level transaction and includes a field (74) that identifies a higher-level 'undo' transaction whereby the subtransaction can be undone without individually undoing its constituent operations. By logging operations in this manner, the database can handle multi-level recovery with very few restrictions on the timing of its updates and log entries.