Join Stage Vs Merge Stage in DS- Parallel JOB

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dgokulakrishnan
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Join Stage Vs Merge Stage in DS- Parallel JOB

Post by dgokulakrishnan »

Could you please explain the difference between Join Stage and Merge Stage..

I could understand that both the stages work based on the Key Column and they take multiple input links. But what is the exact difference between each of them.

I have searched in the forum and found a similar post but it does not provide much information.
Thanks & Regards,

Gokula Krishnan
prasson_ibm
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Post by prasson_ibm »

Merge Stage has one master and multiple update links and that many number of reject links possible.
Join Stage can have multiple input links and only one output link and it can not have reject links.For Full outer join it can have only two input links.

You can perform Inner,Left,right and full outer join using Join Stage but using merge stage only Inner and Left Outer(Consider left as master link) join is possible.

In Merge Stage key field of master link should have unique records.
chulett
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Post by chulett »

Did you check the documention? From what I recall the differences between those two stages are a specific area of discussion there...
-craig

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