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When creating new objects in spoon there's two possibilities: Job and Transfromation. They've got a different set of possible components (although with some level of overlap) and the XML that is generated looks very similar. What's the difference between these two?

nelsonda
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2 Answers2

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This is what I had most problems to understand when starting with Pentaho as well.

  • A job has one start place, and executes one step at a time, with one flow through the steps.

  • A transformation has many possible start places and all steps execute in parallel. If a step has a step before it, it will take the data in there, and use it.

In my use I usually schedule jobs, to run transformations in process to get and transform data.

This is a normal question so it's in the FAQ.

bolav
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    The OP is right the lines are blurred these days. especially now that a transformation can itself execute a job :o) But fundamentally the job is just workflow/prep tasks, and the trans is where you do your real work! – Codek Mar 15 '16 at 07:49
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    @Codek: If I can always get the tasks done by ordered transformations, do I still need to use the jobs? If yes, what should be the use case that I have to use the jobs? – mingchau Apr 09 '19 at 09:13
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    of course not. there's nothing wrong with just having transformations if that's what you need! Also ; Transformations can call jobs as well! – Codek Apr 21 '19 at 17:43
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Turns out the answer is in the FAQ. From the Pentaho FAQ:

Q: In Spoon I can make jobs and transformations, what's the difference between the two?

A: Transformations are about moving and transforming rows from source to target. Jobs are more about high level flow control: executing transformations, sending mails on failure, transferring files via FTP, ...

Another key difference is that all the steps in a transformation execute in parallel, but the steps in a job execute in order.

nelsonda
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