Definition of parameters: selection and transformation - 7.3

Talend Change Data Capture User Guide

Talend Change Data Capture
Talend Change Data Capture
Data Governance > Third-party systems > Database components (Integration) > Change Data Capture
Data Quality and Preparation > Third-party systems > Database components (Integration) > Change Data Capture
Design and Development > Third-party systems > Database components (Integration) > Change Data Capture
Last publication date

You can define the parameters from any Windows machine with a LAN or remote connection (even through the Internet).

There is no limit to the number of machines for which you define the parameters. The parameters are stored on the source machine. The target machine automatically receives the source machine parameter definition. You can modify the parameters as long as the replications are enabled. Your changes are applied when you restart the machine

The parameter definition is structured by environment so that you can separate the various applications handled by Talend Change Data Capture in your company, i.e., one environment for Backup that is set up and monitored by the operation team, one environment for synchronizing an eBusiness that is set up and monitored by another team, one environment for loading a decision support system that is set up and monitored by the decision-support team, one environment for inter-application synchronization, and so forth.

The test and production environment concepts are also integrated, and automatic processes can be triggered when changing over from the test environment to production. Talend Change Data Capture defines replication models so that one parameter definition can be used for distributing to several targets. With overrides (user-defined default values), you can define a scalable and easy-to-maintain set of parameters. The parameter definition procedure has been designed specifically to make this step extremely quick and adaptable.

The context-sensitive help available for writing and setting up the selection/transformation script parameters makes this phase quick and simple. All you need to do is specify the structure of the desired target record where appropriate and how to obtain it from the source. The selections can be made on all or part of the source record, its former values and the context, namely the operation type (addition, modification, deletion), the operator (user, program, Job) and the time factor (date, time with millisecond precision). This allows for deletions, to be taken into account unless they are performed by the year-end purge program. This way, the size of maintained history can be larger on the datawarehouse than on the production machine.

You can change the context, for example, to transform a physical deletion performed on the production machine to a logical deletion (modification) on the datawarehouse, or to obtain a table containing the trace of all the transactions that occurred on a given source table.

The user-defined program call feature is used to call your programs in order to reuse, for example, the routines defined in your company for making selections by applying complex rules, and/or to retrieve the available data in another format.

The Talend Change Data Capture parameters database is open and documented so that you can work with it directly and write to the program that manipulates it directly so as to automate certain functions, run checks and integrate it in a cross-reference tool for performing impact analyses.

Talend Change Data Capture can also be used to trigger scripts and to start programs on the target machine at identifiable times. This is useful, in triggering the recalculation of a multi-dimensional cube right after the data updated on the target machine by a source machine batch has been replicated.

Talend Change Data Capture integrates a distribution method (broadcast) in the non-connected mode, used to load data according to set schedules in non-connected target machines such as, shops, sales force, and partners.

For more information on the procedure to define parameters, see Preparation of the distribution.