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HBase >> mail # user >> Writing MR-Job: Something like OracleReducer, JDBCReducer ...


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Re: Writing MR-Job: Something like OracleReducer, JDBCReducer ...
Michel,

Sorry can you please help me understand what you mean when you say that when
dealing with HBase, you really dont want to use a reducer? Here, Hbase is
being used as the input to the MR job.

Thanks
Sonal
On Fri, Sep 16, 2011 at 2:35 PM, Michel Segel <[EMAIL PROTECTED]>wrote:

> I think you need to get a little bit more information.
> Reducers are expensive.
> When Thomas says that he is aggregating data, what exactly does he mean?
> When dealing w HBase, you really don't want to use a reducer.
>
> You may want to run two map jobs and it could be that just dumping the
> output via jdbc makes the most sense.
>
> We are starting to see a lot of questions where the OP isn't providing
> enough information so that the recommendation could be wrong...
>
>
> Sent from a remote device. Please excuse any typos...
>
> Mike Segel
>
> On Sep 16, 2011, at 2:22 AM, Sonal Goyal <[EMAIL PROTECTED]> wrote:
>
> > There is a DBOutputFormat class in the org.apache,hadoop.mapreduce.lib.db
> > package, you could use that. Or you could write to the hdfs and then use
> > something like HIHO[1] to export to the db. I have been working
> extensively
> > in this area, you can write to me directly if you need any help.
> >
> > 1. https://github.com/sonalgoyal/hiho
> >
> > Best Regards,
> > Sonal
> > Crux: Reporting for HBase <https://github.com/sonalgoyal/crux>
> > Nube Technologies <http://www.nubetech.co>
> >
> > <http://in.linkedin.com/in/sonalgoyal>
> >
> >
> >
> >
> >
> > On Fri, Sep 16, 2011 at 10:55 AM, Steinmaurer Thomas <
> > [EMAIL PROTECTED]> wrote:
> >
> >> Hello,
> >>
> >>
> >>
> >> writing a MR-Job to process HBase data and store aggregated data in
> >> Oracle. How would you do that in a MR-job?
> >>
> >>
> >>
> >> Currently, for test purposes we write the result into a HBase table
> >> again by using a TableReducer. Is there something like a OracleReducer,
> >> RelationalReducer, JDBCReducer or whatever? Or should one simply use
> >> plan JDBC code in the reduce step?
> >>
> >>
> >>
> >> Thanks!
> >>
> >>
> >>
> >> Thomas
> >>
> >>
> >>
> >>
>