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Pig, mail # user - IOException appearing during dump but not illustrate


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Re: IOException appearing during dump but not illustrate
Kris Coward 2010-12-08, 23:19

That looks to have worked. Thanks.

On Wed, Dec 08, 2010 at 02:04:07PM -0800, Dmitriy Ryaboy wrote:
> Try explicitly casting argMap#'s' to a chararray?
>
>
> On Wed, Dec 8, 2010 at 1:53 PM, Kris Coward <[EMAIL PROTECTED]> wrote:
>
> > Hi,
> >
> > I've recently gotten stumped by a problem where my attempts to dump the
> > relations produced by a GROUP command give the following error (though
> > illustrating the same relation works fine):
> >
> > java.io.IOException: Type mismatch in key from map: expected
> > org.apache.pig.impl.io.NullableBytesWritable, recieved
> > org.apache.pig.impl.io.NullableText
> >        at
> > org.apache.hadoop.mapred.MapTask$MapOutputBuffer.collect(MapTask.java:807)
> >        at
> > org.apache.hadoop.mapred.MapTask$OldOutputCollector.collect(MapTask.java:466)
> >        at
> > org.apache.pig.backend.hadoop.executionengine.mapReduceLayer.PigMapReduce$Map.collect(PigMapReduce.java:108)
> > .
> > .
> > .
> >
> > for a little background, the relation that's failing is called y5, and
> > is produced by the following string of commands (in grunt):
> >
> > y2 = foreach y1 generate $0 as timestamp, myudfs.httpArgParse($1) as
> > argMap;
> > y3 = foreach y2 generate argMap#'s' as uid, timestamp as timestamp;
> > y4 = FILTER y3 BY (uid is not null);
> > y5 = GROUP y4 BY uid;
> >
> > and to get an idea what sort of data is involved, ILLUSTRATE y4 yields:
> >
> >
> > -----------------------------------------------------------------------------------------------------
> > | y1     | timestamp: int | args: bag({tuple_of_tokens: (token:
> > chararray)})                        |
> >
> > -----------------------------------------------------------------------------------------------------
> > |        | 1265950806     | {(s=1381688313),
> > (u=F68FFA1F655FDF494ABA520D95E1D99E), (ts=1265950805)} |
> >
> > -----------------------------------------------------------------------------------------------------
> >
> > -----------------------------------------------------------------------------------------------
> > | y2     | timestamp: int | argMap: map
> >                   |
> >
> > -----------------------------------------------------------------------------------------------
> > |        | 1265950806     | {u=F68FFA1F655FDF494ABA520D95E1D99E,
> > ts=1265950805, s=1381688313} |
> >
> > -----------------------------------------------------------------------------------------------
> > --------------------------------------------
> > | y3     | uid: bytearray | timestamp: int |
> > --------------------------------------------
> > |        | 1381688313     | 1265950806     |
> > --------------------------------------------
> > --------------------------------------------
> > | y4     | uid: bytearray | timestamp: int |
> > --------------------------------------------
> > |        | 1381688313     | 1265950806     |
> > --------------------------------------------
> >
> > The same problem was also produced when the FILTER command was omitted,
> > and the relevant chunk of code in myudfs.httpArgParse is:
> >
> >    StringTokenizer tok = new StringTokenizer((String)pair, "=", false);
> >    if (tok.hasMoreTokens() ) {
> >    String oKey = tok.nextToken();
> >        if (tok.hasMoreTokens() ) {
> >            Object oValue = tok.nextToken();
> >            output.put(oKey, oValue);
> >        } else {
> >            output.put(oKey, null);
> >        }
> >    }
> >
> > If anyone has any insight how I could get this to work, that'd really
> > help me out.
> >
> > Thanks,
> > Kris
> >
> > P.S. For those who remember my earlier post about getting httpArgParse
> > to compile, I took the advice to ditch the InternalMap in favour of a
> > HashMap<String,Object>
> >
> > --
> > Kris Coward                                     http://unripe.melon.org/
> > GPG Fingerprint: 2BF3 957D 310A FEEC 4733  830E 21A4 05C7 1FEB 12B3
> >

--
Kris Coward http://unripe.melon.org/
GPG Fingerprint: 2BF3 957D 310A FEEC 4733  830E 21A4 05C7 1FEB 12B3