SWITCH STAGE

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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Sunshine2323
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Location: Dubai,UAE

SWITCH STAGE

Post by Sunshine2323 »

Hi All, :)

I am exploring the Switch Stage
I have used the Selector Mode as Hash
Though my job is running fine i am not able to understand how the rows are getting distributed among the output links

The help document has the following description for this mode

The incoming rows are hashed on the selector column modulo the number of output links and assigned to an output link accordingly.

Can anyone explain?

Thanks,
Sunshine
kprama
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Post by kprama »

Hi
A switch stage is used to split your input rows in to different targets based on a column value. This works like a case statement in any programming language.
you need to specify the column value and then the link number and the switch will output the row based on that column to that particular link.
This is clearly explained in the Parallel guide with an example.
Sunshine2323
Charter Member
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Posts: 130
Joined: Mon Sep 06, 2004 3:05 am
Location: Dubai,UAE

SWITCH STAGE

Post by Sunshine2323 »

Hi,

Thanks for the reply

But I think u have not understood the question.
:D
Is there a formula that is used by the Hashing algorithm to decide the number or records to be sent to a particular o/p link.

The incoming rows are hashed on the selector column modulo the number of output links and assigned to an output link accordingly.

Please go through the line again.

Thanks,
Sunshine
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