Major Description
Pig MR jobs failures produce misleading error messages because just the first line of the error message is reported. Printing the whole error message is very useful when debugging issues as the current version is very misleading about the source of an issue.
PRINTING WHOLE ERROR MESSAGE:
2012-02-14 21:55:53,936 [main] ERROR org.apache.pig.tools.grunt.Grunt - ERROR 6017: java.io.IOException: Deserialization error: org.apache.hcatalog.data.schema.HCatSchema at org.apache.pig.impl.util.ObjectSerializer.deserialize(ObjectSerializer.java:55) at org.apache.pig.impl.util.UDFContext.deserialize(UDFContext.java:181) at org.apache.pig.backend.hadoop.executionengine.util.MapRedUtil.setupUDFContext(MapRedUtil.java:159) at org.apache.pig.backend.hadoop.executionengine.mapReduceLayer.PigOutputFormat.setupUdfEnvAndStores(PigOutputFormat.java:229) at org.apache.pig.backend.hadoop.executionengine.mapReduceLayer.PigOutputFormat.checkOutputSpecs(PigOutputFormat.java:186) at org.apache.hadoop.mapred.JobClient.submitJobInternal(JobClient.java:811) at org.apache.hadoop.mapred.JobClient.submitJob(JobClient.java:771) at org.apache.hadoop.mapred.jobcontrol.Job.submit(Job.java:378) at org.apache.hadoop.mapred.jobcontrol.JobControl.startReadyJobs(JobControl.java:247) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25) at java.lang.reflect.Method.invoke(Method.java:597) at org.apache.pig.backend.hadoop.executionengine.mapReduceLayer.PigJobControl.mainLoopAction(PigJobControl.java:144) at org.apache.pig.backend.hadoop.executionengine.mapReduceLayer.PigJobControl.run(PigJobControl.java:121) at java.lang.Thread.run(Thread.java:662) Caused by: java.lang.ClassNotFoundException: org.apache.hcatalog.data.schema.HCatSchema at java.net.URLClassLoader$1.run(URLClassLoader.java:202) at java.security.AccessController.doPrivileged(Native Method) at java.net.URLClassLoader.findClass(URLClassLoader.java:190) at java.lang.ClassLoader.loadClass(ClassLoader.java:307) at java.lang.ClassLoader.loadClass(ClassLoader.java:248) at java.lang.Class.forName0(Native Method) at java.lang.Class.forName(Class.java:247) at java.io.ObjectInputStream.resolveClass(ObjectInputStream.java:603) at java.io.ObjectInputStream.readNonProxyDesc(ObjectInputStream.java:1574) at java.io.ObjectInputStream.readClassDesc(ObjectInputStream.java:1495) at java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1731) at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1328) at java.io.ObjectInputStream.readObject(ObjectInputStream.java:350) at java.util.Hashtable.readObject(Hashtable.java:859) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25) at java.lang.reflect.Method.invoke(Method.java:597) at java.io.ObjectStreamClass.invokeReadObject(ObjectStreamClass.java:974) at java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:1848) at java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1752) at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1328) at java.io.ObjectInputStream.readObject(ObjectInputStream.java:350) at java.util.HashMap.readObject(HashMap.java:1030) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25) at java.lang.reflect.Method.invoke(Method.java:597) at java.io.ObjectStreamClass.invokeReadObject(ObjectStreamClass.java:974) at java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:1848) at java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1752) at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1328) at java.io.ObjectInputStream.readObject(ObjectInputStream.java:350) at org.apache.pig.impl.util.ObjectSerializer.deserialize(ObjectSerializer.java:53) ... 15 more
CURRENT ERROR MESSAGE:
Pig Stack Trace
---------------
ERROR 6017: java.io.IOException: Deserialization error: org.apache.hcatalog.data.schema.HCatSchema
org.apache.pig.impl.logicalLayer.FrontendException: ERROR 1066: Unable to open iterator for alias l
at org.apache.pig.PigServer.openIterator(PigServer.java:857)
at org.apache.pig.tools.grunt.GruntParser.processDump(GruntParser.java:655)
at org.apache.pig.tools.pigscript.parser.PigScriptParser.parse(PigScriptParser.java:303)
at org.apache.pig.tools.grunt.GruntParser.parseStopOnError(GruntParser.java:188)
at org.apache.pig.tools.grunt.GruntParser.parseStopOnError(GruntParser.java:164)
at org.apache.pig.tools.grunt.Grunt.exec(Grunt.java:84)
at org.apache.pig.Main.run(Main.java:561)
at org.apache.pig.Main.main(Main.java:111)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.apache.hadoop.util.RunJar.main(RunJar.java:156)
Caused by: org.apache.pig.PigException: ERROR 1002: Unable to store alias l
at org.apache.pig.PigServer.storeEx(PigServer.java:956)
at org.apache.pig.PigServer.store(PigServer.java:919)
at org.apache.pig.PigServer.openIterator(PigServer.java:832)
... 12 more
Caused by: org.apache.pig.backend.executionengine.ExecException: ERROR 6017: java.io.IOException: Deserialization error: org.apache.hcatalog.data.schema.HCatSchema
at org.apache.pig.backend.hadoop.executionengine.mapReduceLayer.MapReduceLauncher.launchPig(MapReduceLauncher.java:301)
at org.apache.pig.PigServer.launchPlan(PigServer.java:1270)
at org.apache.pig.PigServer.executeCompiledLogicalPlan(PigServer.java:1255)
at org.apache.pig.PigServer.storeEx(PigServer.java:952)
... 14 more
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