So what about when after the execution is finished? Does the current
implementation also copies output files from HDFS back to local file system?

On Fri, Mar 7, 2008 at 10:35 PM, Craig Macdonald <[EMAIL PROTECTED]>
wrote:

> No idea, sorry. Try on list?
>
> C
>
> pi song wrote:
> > So what about when after the execution is finished? Does the current
> > implementation also copies output files from HDFS back to local file
> > system?
> >
> > On Fri, Mar 7, 2008 at 1:51 AM, Craig Macdonald <[EMAIL PROTECTED]
> > <mailto:[EMAIL PROTECTED]>> wrote:
> >
> >     Hi Pi,
> >
> >     I have a JIRA on this issue: PIG-102
> >     It needs feedback from the community whether it should be a
> >     configuration property or a high-level command.
> >
> >     Craig
> >
> >     Benjamin Reed wrote:
> >     > This uses the FileLocalizer. All file references are sent
> >     through the
> >     > FileLocalizer. If we are doing MAPREDUCE and a file reference
> >     starts with
> >     > file:, we copy it to a temp file in HDFS before we start the job
> >     and use that
> >     > temp file as the input or output of the map reduce job.
> >     >
> >     > ben
> >     >
> >     > On Thursday 06 March 2008 04:07:41 pi song wrote:
> >     >
> >     >> Dear pig-dev mailling-list,
> >     >>
> >     >> I just wanna understand this bit quickly. Below is the code from
> >     >> TestMapReduce.java. As you can see the temp file is created in
> >     local
> >     >> machine but I don't understand how Hadoop MapReduce pick up the
> >     file from
> >     >> local file system rather than HDFS?
> >     >>
> >     >>         PigServer pig = new PigServer(MAPREDUCE);
> >     >>         File tmpFile = File.createTempFile("test", ".txt");
> >     >>         PrintStream ps = new PrintStream(new
> >     FileOutputStream(tmpFile));
> >     >>         for(int i = 0; i < 10; i++) {
> >     >>             ps.println(i+"\t"+i);
> >     >>         }
> >     >>         ps.close();
> >     >>         String query = "foreach (load 'file:"+tmpFile+"')
> >     generate $0,$1;";
> >     >>         System.out.println(query);
> >     >>         pig.registerQuery("asdf_id = " + query);
> >     >>         try {
> >     >>             pig.deleteFile("frog");
> >     >>         } catch(Exception e) {}
> >     >>
> >     >> Cheers,
> >     >> Pi
> >     >>
> >     >
> >     >
> >     >
> >
> >
>
>

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