poonam

• Feb 14th, 2007

 

Run time column propagation is used in case of partial schema usage. when we only know about the columns to be processed and we want all other columns to be propagated to target as they are, we check enable RCP option in administrator or output page columns tab or stage page general tab and we only need to specify the schema of tables we are concerned with . According to documentation"Runtime column propagation (RCP) allows DataStage to be flexible aboutthe columns you define in a job. If RCP is enabled for a project, you can justdefine the columns you are interested in using in a job, but ask DataStageto propagate the other columns through the various stages. So suchcolumns can be extracted from the data source and end up on your datatarget without explicitly being operated on in between.Sequential files, unlike most other data sources, do not have inherentcolumn definitions, and so DataStage cannot always tell where there areextra columns that need propagating. You can only use RCP on sequentialfiles if you have used the Schema File property (see ?Schema File? onpage 5-8 and on page 5-31) to specify a schema which describes all thecolumns in the sequential file. You need to specify the same schema file forSequential File Stage 5-47any similar stages in the job where you want to propagate columns. Stagesthat will require a schema file are:? Sequential File? File Set? External Source? External Target? Column Import? Column Export "

pankaj.garg026

 Profile Answers by pankaj.garg026 

• Jan 15th, 2010

 

Run Time Column Propagation can be used with Column Import Stage. If RCP is enabled in our project, we can define only the columns which we are interested in and other rest of the columns datastage will send through various other stages.
This will ensure such columns reach to our Target eventhough they are not used in between of the stages.

Regards,
Pankaj