Data processing: database and file management or data structures – Database design – Data structure types
Reexamination Certificate
2006-05-23
2006-05-23
Rimell, Sam (Department: 2164)
Data processing: database and file management or data structures
Database design
Data structure types
C707S793000
Reexamination Certificate
active
07051051
ABSTRACT:
In a database system, when an operation (a request or a transaction) that modifies one or more rows of a table is performed, multiple images of the row that is being modified (e.g., added, deleted, or updated) is stored in the table. State identifiers are provided to identify the state of each row, such as a “before image” row and an “after image” row. A before image row represents a row before a modification or “mutation” operation is performed. An after image row represents the latest row as processed by a current modification operation. A before image row is retained in each table as long as the transaction that created or updated the row is active. As soon as the transaction commits successfully, the before image rows become reusable and can be reused by another request or transaction. The state identifier associated with each row can also indicate that a “mutation” is not being performed on a row; that is, an operation that modifies the contents of the row is not currently being performed.
REFERENCES:
patent: 5675727 (1997-10-01), Watanabe
patent: 5933838 (1999-08-01), Lomet
patent: 6349310 (2002-02-01), Klein et al.
NCR Corporation, “Introduction to Teradata RDBMS,” V2R4.0/V2R4.0.1, pp. i-xxii-1-1 to 8-14 (Sep. 2000).
NCR Corp.
Rimell Sam
Trop Pruner & Hu P.C.
LandOfFree
Recovering from failed operations in a database system does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Recovering from failed operations in a database system, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Recovering from failed operations in a database system will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3648815