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Hadoop >> mail # user >> Re: Multi-stage map/reduce jobs

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Re: Multi-stage map/reduce jobs
You probably want something like Oozie which provides DAG-like flows
for jobs, so you can easily write in "upon-failure" and "upon-success"
form of conditions, aside of incorporating complex logic as well.

Otherwise, I guess you could do what Jay has suggested, or look at the
JobControl classes to avoid some of the extra work needed.

On Sat, Nov 24, 2012 at 3:52 AM, Sean McNamara
> It's not clear to me how to stitch together multiple map reduce jobs.
> Without using cascading or something else like it, is the method basically
> to write to a intermediate spot, and have the next stage read from there?
> If so, how are jobs responsible for cleaning up the temp/intermediate data
> they create?  What happens if stage 1 completes, and state 2 doesn't, do the
> stage 1 files get left around?
> Does anyone have some insight they could share?
> Thanks.

Harsh J
Radim Kolar 2012-11-25, 16:57