Unable to convert non-flat tuple to string

[mickey hsieh]

Any ideal

here is my script

logs = load '/test/action_log_2008-03-30.log' using PigStorage(',') ;
gs = group logs by ( $1, $2) ;
cs = foreach gs generate group, COUNT ( logs.$1);
store cs into '/test/case1' ;


java.lang.RuntimeException: java.io.IOException: Unable to convert non-flat
tuple to string.
at
org.apache.pig.backend.hadoop.executionengine.mapreduceExec.PigMapReduce$ReduceDataOutputCollector.add(PigMapReduce.java:358)
at
org.apache.pig.impl.eval.collector.UnflattenCollector.add(UnflattenCollector.java:52)
at
org.apache.pig.impl.eval.GenerateSpec$CrossProductItem.add(GenerateSpec.java:232)
at
org.apache.pig.impl.eval.collector.UnflattenCollector.add(UnflattenCollector.java:52)
at
org.apache.pig.impl.eval.collector.DataCollector.addToSuccessor(DataCollector.java:98)
at org.apache.pig.impl.eval.SimpleEvalSpec$1.add(SimpleEvalSpec.java:38)
at
org.apache.pig.impl.eval.GenerateSpec$CrossProductItem.exec(GenerateSpec.java:263)
at org.apache.pig.impl.eval.GenerateSpec$1.add(GenerateSpec.java:88)
at
org.apache.pig.backend.hadoop.executionengine.mapreduceExec.PigMapReduce.reduce(PigMapReduce.java:159)
at org.apache.hadoop.mapred.ReduceTask.run(ReduceTask.java:333)
at org.apache.hadoop.mapred.TaskTracker$Child.main(TaskTracker.java:2084)



-- 
Thanks,
MIckey Hsieh