Modify Stage in parallel jobs

venkates.dw · Post by **venkates.dw** » Fri Apr 10, 2009 7:25 am

hi,

in parallel jobs modify stage, one of the option is keep column.. what is use of keep column.. give me some explanation with small example

Thanks in Advance....

chulett · Post by **chulett** » Fri Apr 10, 2009 7:33 am

Why not just read the chapter on the Modify Stage in the Parallel Job Developer's Guide pdf? Got examples and everything.

ray.wurlod · Post by **ray.wurlod** » Fri Apr 10, 2009 9:51 am

Any columns you don't KEEP or otherwise derive are dropped.

Any columns you don't DROP are kept.

The two are mutually exclusive, a point which is not well made in the Parallel Job Developer's Guide manual but is well made in the Orchestrate Operators manual.

venkates.dw · Post by **venkates.dw** » Mon Apr 13, 2009 1:54 am

Hi, in modify we can perform drop column. keep column . these manipulations we can perform in transform stage, then what is need of this modify stage especially.. Please clarify ..

Thank you,

mahadev.v · Post by **mahadev.v** » Mon Apr 13, 2009 3:01 am

Modify stage does not create extra processes. It runs on the output link of the previous stage. So it would be slightly faster than a transformer. AFAIK, the RCP option in each stage also creates a modify operator to propagate or drop the columns.