Bmc Software, Inc.

Michael S Murley

Thomas G Price

Stanley James Dee

Kenneth M McDonald

Linda S Ball

William J Pothoff

Richard T Weaver

Stanley D Dee

A copy utility creates a copy of source database objects that is transactionally consistent to a consistent point-in-time, and a recovery utility applies log records to the consistent copy to make a resulting image that is updated as of an identified point-in-time (i.e., the current time or a point-in-time after the copy was made). To effectively recover and apply the logs so that no previously in-flight transactions are lost, the copy utility registers a starting point indicating a point-in-time for logs to be applied to the copy and also registers a smallest lock size used to block access to target data when the copy was made. The recovery utility bases its recovery operations using the registered starting point and the smallest lock size when applying log records to the copy so as not to lose any previously in-flight transactions.

Database recovery using logs applied to consistent copies

An online index building operation is disclosed for building an index from source data with minimal loss of availability to the source data. The source data can be maintained in a relational database system, such as in a tablespace of a DB2&#xae; environment. The disclosed operation creates a consistent image of the source data as of a point-in-time and creates an index from the consistent image. Then, the disclosed operation repeats the acts of making the image consistent as of a subsequent point-in-time and updating the index to reflect the subsequent consistent image until substantially caught up with the current changes to the source data. If not caught up, the disclosed operation continues unless it is falling behind at which point the operation terminates. If it is caught up, the disclosed operation locks access to the source data, updates the image to reflect any final changes, updates the index, and allows access to the index.

Method and apparatus for building index of source data

Techniques to create physically and transactionally consistent copies of one or more database objects without impacting the availability of the target database objects are described. In one technique, a consistent copy is created as of the time a copy utility is executed. In another technique, a consistent copy is created as of an arbitrary specified time. This approach modifies a prior copy to bring it 'up-to-date.' In yet another technique, a consistent copy is created by starting with a current snapshot of the target database objects and selectively removing updates from it back to a user specified arbitrary point-in-time. Each of the described techniques generate consistent copies of the target database objects without blocking users from accessing the target objects during the copy operation.

Unobtrusive point-in-time consistent copies

Growing community of inventors

Austin, TX, United States of America

Michael S Murley