Some insight on InfoSphere DataStage OSH

Use can create InfoSphere DataStage jobs by logging into its client "Designer". On compilation of the Job its gets converted into parallel job flows, and reusable components that execute on the parallel Information Server engine. These generated flows are meant for extracting, cleansing, transforming, integrating, and loading data into target files, target systems, or packaged applications.For any Parallel Job, InfoSphere DataStage generates the OSH (Orchestrate Shell Script) and C++ code for any Transformer stages used.
To summarize Designer performs the following tasks:
 More on OSH:
How it is represented
The real execution order of operators is dictated by input/output designators, and not by their placement on the diagram. The data sets connect the OSH operators. These are “virtual data sets”, that is, in memory data flows. Link names are used in data set names — it is therefore good practice to give the links meaningful names.

-Ritesh 
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