Bmc Software, Inc.

William J Pothoff

Thomas G Price

Richard Wayne Cline

Vladimir Prasolov

Stanley James Dee

Michael S Murley

James L Whisenant

Konstantin Lavren Bobovich

James T Rabbitt

A captured sequence of log records for a copy of a database may be inspected to identify an obviating log record at a captured sequence position of the captured sequence and related to a page of the plurality of pages, the obviating log record corresponding to an obviating change that replaces an earlier change of an earlier log record. The captured sequence of log records may be sorted into an applied sequence of log records for applying changes of the sequence of changes, in which the obviating log record is moved from the captured sequence position to an applied sequence position that is prior to the earlier sequence position of the earlier log record. The database may then be recovered using the applied sequence of log records.

Optimization of log record application during database recovery

A method to efficiently create a consistent image of a database index at any point-in-time by reversing the effect of uncommitted updates by applying database transaction logs to an index page set in a single pass. The created image can be used to recover the database index to a point in time that is consistent with its associated table, or for physical migration where data and indexes are migrated to another database that may or may not be on the same DBMS and the indexes and data must be consistent as of the same point in time.

Systems and methods for recovery of consistent database indexes

In one aspect, a computer-implemented method for ensuring a source database (e.g., target space or index space) has correct version information before a migration includes executing, using at least one processor, instructions recorded on a computer-readable storage medium. The instructions include determining whether a table has been changed since a most recent alter of the table, performing an update on the table when it is determined that the table has not been changed since the most recent alter, and performing a rollback on the table after the update. The method may also include creating an image copy of the data in the source database and refreshing data in a target database with the image copy of the data in the source database. The method may also include automatically repairing the target database when the version information of the target does not correspond with the version information for the source.

Systems and methods for migrating database data

The present description refers to a computer implemented method, computer program product, and computer system for receiving a start time, selecting one or more database objects for which a database recovery progress report is to be provided, determining, based on an object recovery table generated by the database recovery utility, which of the selected database objects have been recovered since the start time, and outputting a database recovery progress report that identifies at least a number or percentage of the selected database objects that have been recovered by the database recovery utility since the start time.

Database recovery progress report

In one general aspect, a computer-implemented method for migrating data from a source database to a target database includes a computer-implemented method that includes executing, using at least one processor, instructions recorded on a non-transitory computer-readable storage medium. The method includes ensuring that the source database has correct version information, creating an image copy of the data in the source database, and collecting metadata describing the source database. The metadata may include information used to verify that the target database is compatible with the source database, to automatically translate object identifiers, and to avert the migration if no data has changed in the source and the target databases (e.g., table and index spaces) since a previous migration. The method may further include refreshing the data in the target database using the image copy after determining that the source database and the target database are compatible.

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.

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Austin, TX, United States of America

William J Pothoff