Sort Stage Query

Post questions here relative to DataStage Enterprise/PX Edition for such areas as Parallel job design, Parallel datasets, BuildOps, Wrappers, etc.

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udayk_2007
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Sort Stage Query

Post by udayk_2007 »

Hello guys

Can anybody please clarify ,what is the difference between 'Create cluster Key Change Column' and 'Create Key Change Column' option in Sort Stage ?

From reading the doc,both the options looks similar.

Thanks in advance for your help

Regards
Ulhas
sacheens23
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Re: Sort Stage Query

Post by sacheens23 »

jiegao
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Re: difference between CCKCC and CKCC

Post by jiegao »

How do we know if the data are "previously grouped"? "Previously Sorted" is easy to understand. I have a job contains JOIN stage followed by Sort stage. Data are sorted using link sort before the JOIN stage. Can I use "Previously Goruped" option? Why cannot use "Previously Sorted" option? Thanks in advance.
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Jie
prakashdasika
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Post by prakashdasika »

If you only partition on a key and do not sort, it is 'grouped'. If you do partition and sort on the key then it is 'sorted'.

If the sort keys in the sort stage are same as the sort keys in join stage then you need to use - Create Cluster Key Change Column (Don't sort previously sorted) , If the keys are different, define the new keys and use - Create Key Change Column.
Prakash Dasika
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jiegao
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Post by jiegao »

Thanks prakashdasika for your answer. That is exactly what I was curious about.
ray.wurlod
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Post by ray.wurlod »

Please mark this thread as Resolved
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