Checking Operator Error

sudharma · Post by **sudharma** » Mon Jan 29, 2007 12:33 pm

Hi everyone ,

I get this Error when i run a job .

seq_rej: When checking operator: A sequential operator cannot preserve the partitioning of the parallel data set on input port 0.

i really dont understand what this error means exactly. can anyone guide me how to work on this warning message when i run this job

thanks a lot

ray.wurlod · Post by **ray.wurlod** » Mon Jan 29, 2007 3:43 pm

Your job asks to preserve partitioning. A Sequential File that is writing must collect all partitions into a single stream and therefore can not preserve partitioning.

In the stage that precedes (feeds) the Sequential File stage, check the value of the Preserve Partitioning flag. Set it to "Clear".

Make sure also that the execution mode of the Sequential File stage is sequential, not parallel.

koolnitz · Post by **koolnitz** » Tue Jan 30, 2007 3:35 pm

Make sure also that the execution mode of the Sequential File stage is sequential, not parallel

Ray, does a sequential file stage support Parallel execution mode? I've never seen this option changeable - it's always greyed out (no-change mode) in all the sequential file stages used in my project. Do we need to change some setting to enable this option?

Thanks in advance!

ray.wurlod · Post by **ray.wurlod** » Tue Jan 30, 2007 3:40 pm

A Sequential File stage supports parallel execution when reading multiple files. If you have only one File property and have not selected multiple readers per node, the parallel option will be disabled.

koolnitz · Post by **koolnitz** » Tue Jan 30, 2007 3:56 pm

seq_rej: When checking operator: A sequential operator cannot preserve the partitioning of the parallel data set on input port 0.

I see. Got confused because the OP mentioned about the Seq file stage used as a target. I believe what you just explained is applicable to seq file stages used as source.

Thank you!

ray.wurlod · Post by **ray.wurlod** » Tue Jan 30, 2007 6:13 pm

Even when used as a target a Sequential File stage may have multiple File properties, writing to different files. In this case it will execute in parallel mode unless constrained to do otherwise.