Currently using Pig 0.8 and Hadoop 0.20.2. I'm able to run things in local
mode as well as run fs -* commands from within Grunt running in MapReduce
mode. I can't seem to be able to execute any Pig Latin statement in
MapReduce mode. The fact that I can browse HDFS and access files leads me to
believe that the setup is correct (also verified by the correct namenode and
jobtracker addresses connected to when firing off any pig command). I don't
know why though I can't run anything else. A simple command like the
following:
data = LOAD 'test.csv' USING PigStorage(',');
DUMP data;
Produces the following stack trace:
Pig Stack Trace
---------------
ERROR 1066: Unable to open iterator for alias data
org.apache.pig.impl.logicalLayer.FrontendException: ERROR 1066: Unable to
open iterator for alias data
at org.apache.pig.PigServer.openIterator(PigServer.java:754)
at
org.apache.pig.tools.grunt.GruntParser.processDump(GruntParser.java:612)
at
org.apache.pig.tools.pigscript.parser.PigScriptParser.parse(PigScriptParser.java:303)
at
org.apache.pig.tools.grunt.GruntParser.parseStopOnError(GruntParser.java:165)
at
org.apache.pig.tools.grunt.GruntParser.parseStopOnError(GruntParser.java:141)
at org.apache.pig.tools.grunt.Grunt.run(Grunt.java:76)
at org.apache.pig.Main.run(Main.java:465)
at org.apache.pig.Main.main(Main.java:107)
Caused by: java.io.IOException: Job terminated with anomalous status FAILED
at org.apache.pig.PigServer.openIterator(PigServer.java:744)
... 7 more
Any other more elaborate collection of Pig statements will produce this:
Pig Stack Trace
---------------
ERROR 2244: Job failed, hadoop does not return any error message
org.apache.pig.backend.executionengine.ExecException: ERROR 2244: Job
failed, hadoop does not return any error message
at org.apache.pig.tools.grunt.GruntParser.executeBatch(GruntParser.java:116)
at
org.apache.pig.tools.grunt.GruntParser.parseStopOnError(GruntParser.java:169)
at
org.apache.pig.tools.grunt.GruntParser.parseStopOnError(GruntParser.java:141)
at org.apache.pig.tools.grunt.Grunt.exec(Grunt.java:90)
at org.apache.pig.Main.run(Main.java:510)
at org.apache.pig.Main.main(Main.java:107)
Where any input file is flagged as unreadable by the following error message
during execution:
Input(s):
Failed to read data from "test.csv"
All files are accessible in MapReduce mode via cat, ls etc. I might be
missing something very obvious here since this is the first time I've used
Pig so any help would be greatly appreciated.
- Dimitris
