For InfoSphere™ QualityStage® upgrades...special considerations

InfoSphere™ Information Server8 represents a very significant move forward for IBM’s data integration platform. For the first time QualityStage® stages are native on the DataStage® parallel canvas. This means QualityStage® and DataStage® are literally the same design, compilation and run time environment. For customers with QualityStage® applications on previous releases there needs to be a careful evaluation of the most effective approach to moving to the QualityStage® / DataStage®8 platform.

Information Server 8 is a new platform architecture and features the porting of the previously independent QualityStage server environment as native stages on the DataStage parallel canvas. The QS migration utility has four modes of operation:

• Legacy Operational Mode – the QS7.5 project is converted into a single QS8 Legacy Stage with sequential input and output stages. The Legacy Stage effectively encapsulates the QS7.5 runtime environment and ensures that the same input produces the same output in QS8 as in QS7.5. Legacy Stage is ideal for long standing stable QS applications that do not need to be edited or expanded. However the Legacy Stage cannot be edited and will not work for QS7.5 stages CASS, SERP, PGM, MNV, WAVES and Format Convert.
• Expanded Mode – the QS7.5 project is converted into a QS job with a mix of QS8 "native" stages and Legacy stages. Expanded mode attempts to make stage conversions into QS8 stages where possible.
• Standardization Rule Set Mode – converts standardization rule sets.
• Match Specification Mode – converts Match and Unduplication match specifications.

As a production ready implementation of QualityStage8 PQI can be an excellent alternative to migrating and re-building an earlier QualityStage version application in QS8. An easy proof is to take the source data to the current QS application, run it through PQI and compare the PQI results to the output of your current QS application. It may be easier and faster to customize the PQI package to meet your specific requirements than to migrate your 7.x application to version 8 and then make the necessary modifications. At the same time PQI delivers valuable additional functions.

Customization of the PQI package can bring forward important parts of your current QS application. For example the standardization rule sets and match specifications from the QS7.5 application can be "hot swapped" and integrated with PQI. The post processing logic written in QS7.5 can be implemented as a post processing module that uses the PQI standard output.

The basic set of tasks for QS upgrade to version 8 with PQI are:

• install QS8 and PQI
• run full volumes through PQI / QS8 with the current source data
• compare the output of PQI with the current QS7.5 application
• evaluate deltas and confirm PQI / QS8 design specifications
• migrate and integrate relevant QS7.5 jobs to QS8
• customize the PQI package including "hot swapping" standardization rules and match specifications as required
• complete post processing
• run volume tests

Because PQI out of the box is a complete production application, the installation and full volume run can be done very quickly to inform a gap analysis and determine the best way to implement and take advantage of DataStage / QualityStage8.