International Business Machines Corporation

Adil Mohammad Sardar

David Tremaine

Philip Shawn Cox

Leo Tat Man Lau

Leo T M Lau

Ivan Lew

Aleksandrs Santars

Marko Milek

Leo Lau

A method and system for facilitating an undo operation. In one embodiment, the method includes generating a plurality of control files, where each of the control files is associated with a batch of data that is received from a sending partition during a redistribution process, and where each control file includes a list of pages and corresponding ranges of rows of data that have been appended to the pages. The method also includes writing the control files to a persistent memory for each control file where all of the associated rows of the respective consistency point have been appended to pages and written to a persistent memory. The method also includes, in response to an interruption in the redistribution process, identifying pages and rows to be deleted during an undo operation based on the plurality of control files.

Efficient undo-processing during data redistribution

Techniques are described for data redistribution. Embodiments store a first set of receiver location identifiers mapped to a document identifier and assigned to a first set of receiver locations storing relational data referencing the document identifier. Embodiments store a second set of receiver location identifiers mapped to the document identifier and assigned to a second set of receiver locations storing document data corresponding to the document identifier referenced by the relational data. Sender index keys are received separately from the relational data and the document data, the sender index keys referencing the document identifier and containing sender location identifiers. Embodiments determine, from the first set of receiver location identifiers and the second set of receiver location identifiers, which receiver location identifiers are mapped to the document identifier referenced by the sender index keys. The sender location identifiers are then replaced with the determined receiver location identifiers.

Redistribute native XML index key shipping

Techniques are described for data redistribution in a database system. Embodiments store a first set of receiver location identifiers mapped to a document identifier, the first set of receiver location identifiers assigned to a first set of receiver locations storing relational data referencing the document identifier. Embodiments further store a second set of receiver location identifiers mapped to the document identifier, the second set of receiver location identifiers assigned to a second set of receiver locations storing document data corresponding to the document identifier referenced by the relational data. Sender index keys are received separately from the relational data and the document data, the sender index keys referencing the document identifier and containing sender location identifiers. Embodiments determine, from the first set of receiver location identifiers and the second set of receiver location identifiers, which receiver location identifiers are mapped to the document identifier referenced by the sender index keys. The sender location identifiers are then replaced with the determined receiver location identifiers.

A method and system for optimizing data redistribution in a database. In one embodiment, the method includes moving, during a first scan, outgoing records from a sending partition to one or more receiving partitions, where free space is created in the sending partition due to the outgoing records leaving the sending partition. The method also includes filling, during the first scan, some of the free space with remaining records that do not leave the sending partition.

Dynamic data compaction for data redistribution

The invention relates to a method and apparatus of distributing data in portioned databases operating on a shared-nothing architecture. The invention provides two independent streams of data, where a first stream sends table data, and the second stream sends LOB data, to a receiving partition. The receiving partition re-couples the LOB data with the table data. Using two independent streams to distribute LOB data can increase data redistribution since large amounts of input/output is not performed to handle the sending of LOB data in a coupled fashion.

Method and apparatus of distributing data in partioned databases operating on a shared-nothing architecture

An apparatus and method to streamline updates to an index in a shared-nothing architecture. The apparatus may include an association module, a consolidation module, and a processing module. The association module may associate index update requests with an index. The index update requests may be configured to update the index in response to a redistribution of data in a data table. The consolidation module may compile the index update requests prior to processing and consolidate the index update requests into a smaller number of simplified index update requests to achieve substantially the same result. The processing module may then independently process the simplified index update requests and update the index accordingly.

Apparatus and method for streamlining index updates in a shared-nothing architecture

A transactional database server is accessible by applications. Applications indicate whether access is made using an online protocol. Where the database server determines that a request received from an application is made using the online protocol, the server will return one of a set of defined error codes upon identified system resources being determined to be scarce. Applications monitor responses from the database server for the defined error codes. On receipt of one of the defined error codes an application will issue a commit to the database server to attempt to release system resources for use by applications.

Growing community of inventors

Markham, Canada

Adil Mohammad Sardar