Review Request: project of bags from complex data causes failures

[Daniel Dai <da...@gmail.com>]

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This is an automatically generated e-mail. To reply, visit:
https://reviews.apache.org/r/272/
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Review request for pig and Richard Ding.


Summary
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A = load 'complex data' as (x: bag{});
B = foreach A generate x.($1, $2);

produces stack trace:

2008-10-14 15:11:07,639 [main] ERROR org.apache.pig.backend.hadoop.executionengine.mapReduceLayer.Launcher - Error message from task (reduce) task_200809241441_9923_r_000000java.lang.NullPointerException
at org.apache.pig.backend.hadoop.executionengine.physicalLayer.expressionOperators.POProject.getNext(POProject.java:183)
at org.apache.pig.backend.hadoop.executionengine.physicalLayer.relationalOperators.POForEach.processPlan(POForEach.java:215)
at org.apache.pig.backend.hadoop.executionengine.physicalLayer.relationalOperators.POForEach.getNext(POForEach.java:166)
at org.apache.pig.backend.hadoop.executionengine.mapReduceLayer.PigMapReduce$Reduce.runPipeline(PigMapReduce.java:252)
at org.apache.pig.backend.hadoop.executionengine.mapReduceLayer.PigMapReduce$Reduce.reduce(PigMapReduce.java:222)
at org.apache.pig.backend.hadoop.executionengine.mapReduceLayer.PigMapReduce$Reduce.reduce(PigMapReduce.java:134)
at org.apache.hadoop.mapred.ReduceTask.run(ReduceTask.java:318)
at org.apache.hadoop.mapred.TaskTracker$Child.main(TaskTracker.java:2207)

PIG-496-1.patch is depended on PIG-730. Otherwise there will be frontend exception. 


This addresses bug PIG-496.
    https://issues.apache.org/jira/browse/PIG-496


Diffs
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  http://svn.apache.org/repos/asf/pig/trunk/src/org/apache/pig/builtin/Utf8StorageConverter.java 1057393 
  http://svn.apache.org/repos/asf/pig/trunk/test/org/apache/pig/test/TestConversions.java 1057393 

Diff: https://reviews.apache.org/r/272/diff


Testing
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Test-patch:
     [exec] +1 overall.  
     [exec] 
     [exec]     +1 @author.  The patch does not contain any @author tags.
     [exec] 
     [exec]     +1 tests included.  The patch appears to include 3 new or modified tests.
     [exec] 
     [exec]     +1 javadoc.  The javadoc tool did not generate any warning messages.
     [exec] 
     [exec]     +1 javac.  The applied patch does not increase the total number of javac compiler warnings.
     [exec] 
     [exec]     +1 findbugs.  The patch does not introduce any new Findbugs warnings.
     [exec] 
     [exec]     +1 release audit.  The applied patch does not increase the total number of release audit warnings.

Unit-test
    all pass


Thanks,

Daniel