Order of execution in transformer stage?

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iamnagus
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Order of execution in transformer stage?

Post by iamnagus »

I have a parallel job in which have the stage variables and constraints. I just want to know the order of the execution in transformer stage?
Can any one give idea? Thanks in advance.
Ratan Babu N
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Re: Order of execution in transformer stage?

Post by Ratan Babu N »

iamnagus wrote:I have a parallel job in which have the stage variables and constraints. I just want to know the order of the execution in transformer stage?
Can any one give idea? Thanks in advance.
First stage variables will execute and then constraints
balajisr
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Post by balajisr »

It is documented in transformer stage of parallel job developer's guide. Read the documentation.
kumar_s
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Post by kumar_s »

Another work of full Wurlod for Server transformer

Code: Select all

1. Any before-stage subroutine is executed.  If ErrorCode is non-zero, the job aborts. 
2. A row is obtained from the stream input link. 
3. For each reference input link, in the specified execution order: 
   (a) the reference key expression is evaluated 
   (b) a "get by key" request is issued (this handles supply of NULL values if that record is not found 
4. Stage variables are evaluated in the order in which they appear in their grid. 
5. The REJECTED variable is set to TRUE 
6. For each output link, in the specified execution order: 
   (a) the output link constraint expression is evaluated 
   (b) if the output link constraint expression is satisfied, column derivation expressions on that link are evaluated then a "put" request is issued and the REJECTED variable is set to FALSE 
   (c) if the output link is marked as handling rejects, and the REJECTED variable is TRUE, column derivation expressions on that link are evaluated then a "put" request is issued 
7. If the row count reaches a particular value, the stage's status record in the RT_STATUSnn table for the job is updated 
8. If the "end of data" token has not been received, go back to step 2. 
9. Any after-stage subroutine is executed.  If ErrorCode is non-zero, the job aborts.
Just skip the lookup option, since its not possiblein PX. :wink:
Impossible doesn't mean 'it is not possible' actually means... 'NOBODY HAS DONE IT SO FAR'
ray.wurlod
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Post by ray.wurlod »

Reporting row count and/or interval may be specified by environment variables for parallel jobs.
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