International Business Machines Corporation

Christian Michel

Daniel Martin

Vassil Radkov Dimov

Knut Stolze

John Marland Garth

Namik Hrle

Bryan Frederick Smith

Sowmya Kameswaran

Manogari Nogi Simanjuntak

David R Betten

Timm Zimmermann

A method for executing a query on a target database against the most recent source data is disclosed. The method comprises maintaining linked—i.e., at least partially synchronized—databases comprising a source and a target database. The method comprises receiving a direct query against a table in the target database, the query comprising a request for using the most recent source data and requesting by the target database from the source database a status about latest data regarding the table. Upon the status indicating that data in the table do not correspond to the most recent data, the method comprises waiting up to a predefined time period for the most recent data of the table to be synchronized from the source database to the target database, and upon the data of the table not being synchronized within the predefined time period, the method comprises issuing a timeout signal.

Query execution on a replicated database with most recent data

The present disclosure relates to a method for data synchronization between a source database system and target database system, wherein execution of a database transaction of the source database system is complete if a processing step followed by an application step of the database transaction is performed. For each identified database transaction, a processing step and/or application step may be performed.

Data synchronization between a source database system and target database system

Methods, computer program products, and systems are presented. The method computer program products, and systems can include, for instance: receiving by primary database system a query statement that references a first table, wherein the primary database system is associated to a first accelerator database system and a second accelerator database system, wherein modifications performed on tables of the primary database system are iteratively replicated into the first accelerator database system and the second accelerator database system; examining latency data that specifies a latency with which a modification to the first table has been replicated into the first accelerator database system and a latency with which a modification to the first table has been replicated into the second accelerator database system; selecting, in dependence on the examining, the first accelerator database system for execution of the query statement; routing the query statement to the first accelerator database system for execution in response to the selecting.

Reduced latency query processing

According to one embodiment, a method, computer system, and computer program product for data synchronization between a source database system and a target database system, the source database system including a source dataset and the target database system including a target dataset that is configured to include a copy of the source dataset. The embodiment may include configuring the target database system to detect data changes in the source dataset. The embodiment may include applying the detected data changes on the target dataset.

Data synchronization in a data analysis system

Techniques are described for assigning collections of records to parallel processing tasks for sorting index keys of the records. In one example, a method includes determining an order of the collections of records in a descending order by byte length of an index key of each of the collections of records. The method further includes modifying the order of the collections of records in a descending order, for collections of records with index keys of equal byte length, by number of records per collection of each of the collections of records with index keys of same byte length. The method further includes assigning the collections of records to a plurality of parallel processing tasks in the order of the collections of records. The method may combine low elapsed processing times by balancing the amount of work in each assigned processing task with reduced computing resource overhead for each processing task.

Sorting database collections for parallel processing

An apparatus, system, and method for determining the maximum supported degree of parallel sort operations in a multi-processor computing environment. An allocation module allocates a minimum number of sort files to a sort operation for each data source that participates in the parallel sort. The allocation module attempts to allocate sort files of one-half the sort operation data source file size, and iteratively reduces the sort file size requests in response to determinations that sort files of the requested size are not available. After allocation, a parallel operation module determines whether there is sufficient virtual storage to execute the sort operations in parallel. If there is not, the parallel operations module collapses the two smallest sort operations, thereby reducing the degree of parallelism by one, and repeats the request. The parallel operation module repeats the process until the sorts are executed or the process fails for lack of virtual storage.

Growing community of inventors

Sindelfingen, Germany

Christian Michel