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Pig >> mail # user >> how to load custom Writable class from sequence file?


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Yang 2013-09-17, 00:37
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Re: how to load custom Writable class from sequence file?
The problem is that pig only speaks its data types. So you need to tell it
how to translate from your custom writable to a pig datatype.

Apparently elephant-bird has some support for doing this type of thing...
take a look at this SO post
http://stackoverflow.com/questions/16540651/apache-pig-can-we-convert-a-custom-writable-object-to-pig-format
On Mon, Sep 16, 2013 at 5:37 PM, Yang <[EMAIL PROTECTED]> wrote:

> I tried to do a quick and dirty inspection of some of our data feeds, which
> are encoded in gzipped SequenceFile.
>
> basically I did
>
> a = load 'myfile' using ......SequenceFileLoader() AS ( mykey, myvalue);
>
> but it gave me some error:
> 2013-09-16 17:34:28,915 [Thread-5] INFO
>  org.apache.hadoop.io.compress.CodecPool - Got brand-new decompressor
> 2013-09-16 17:34:28,915 [Thread-5] INFO
>  org.apache.hadoop.io.compress.CodecPool - Got brand-new decompressor
> 2013-09-16 17:34:28,915 [Thread-5] INFO
>  org.apache.hadoop.io.compress.CodecPool - Got brand-new decompressor
> 2013-09-16 17:34:28,961 [Thread-5] WARN
>  org.apache.pig.piggybank.storage.SequenceFileLoader - Unable to translate
> key class com.mycompany.model.VisitKey to a Pig datatype
> 2013-09-16 17:34:28,962 [Thread-5] WARN
>  org.apache.hadoop.mapred.FileOutputCommitter - Output path is null in
> cleanup
> 2013-09-16 17:34:28,963 [Thread-5] WARN
>  org.apache.hadoop.mapred.LocalJobRunner - job_local_0001
> org.apache.pig.backend.BackendException: ERROR 0: Unable to translate class
> com.mycompany.model.VisitKey to a Pig datatype
> at
>
> org.apache.pig.piggybank.storage.SequenceFileLoader.setKeyType(SequenceFileLoader.java:78)
>  at
>
> org.apache.pig.piggybank.storage.SequenceFileLoader.getNext(SequenceFileLoader.java:133)
>
>
> in the pig file, I have already REGISTERED the jar that contains the class
>  com.mycompany.model.VisitKey
>
>
> if PIG doesn't work, the only other approach is probably to use some of the
> newer "pseudo-scripting " languages like cascalog or scala
> thanks
> Yang
>
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Yang 2013-09-17, 01:43
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Pradeep Gollakota 2013-09-17, 01:56
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Pradeep Gollakota 2013-09-17, 02:47
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Yang 2013-09-17, 16:20
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Dmitriy Ryaboy 2013-09-24, 09:22
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John Meagher 2013-09-24, 13:21
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Dmitriy Ryaboy 2013-09-24, 14:58
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Yang 2013-09-24, 17:51