Using RCP With Column Import Stages

Runtime column propagation (RCP) allows InfoSphere® DataStage® to be flexible about the columns you define in a job. If RCP is enabled for a project, you can just define the columns you are interested in using in a job, but ask InfoSphere DataStage to propagate the other columns through the various stages. So such columns can be extracted from the data source and end up on your data target without explicitly being operated on in between.

Columns you are importing do not have inherent column definitions, and so InfoSphere DataStage cannot always tell where there are extra columns that need propagating. You can only use RCP on Column Import stages if you have used the Schema File property to specify a schema which describes all the columns in the column. You need to specify the same schema file for any similar stages in the job where you want to propagate columns. Stages that will require a schema file are:

• Sequential File
• File Set
• External Source
• External Target
• Column Import
• Column Export