Process Avro File with Pig

Must use the compatible piggybank.jar with CDH, for example.

find /opt/cloudera/parcels/ -name *piggybank*.jar
/opt/cloudera/parcels/CDH-4.7.0-1.cdh4.7.0.p0.40/lib/pig/piggybank.jar

Otherwise, the job fails with Error:

java.lang.RuntimeException: java.lang.reflect.InvocationTargetException

Caused by: java.lang.IncompatibleClassChangeError: Found interface org.apache.hadoop.mapreduce.JobContext, but class was expected

at org.apache.pig.piggybank.storage.avro.PigAvroInputFormat.listStatus(PigAvroInputFormat.java:)

Note: 
1. .avsc schema is not necessary. If added, please also upload it in hdfs.
2. The output file is in binary format, probably because avro is in binary.

Sample code:

REGISTER lib/avro-1.7.3.jar
REGISTER lib/json-simple-1.1.1.jar
REGISTER lib/piggybank.jar
REGISTER lib/jackson-core-asl-1.8.5.jar
REGISTER lib/jackson-mapper-asl-1.8.5.jar
REGISTER lib/snappy-java-1.1.1.jar

--delete the output folder
rmf output
avro = LOAD 'xxxx.avro' USING org.apache.pig.piggybank.storage.avro.AvroStorage
('no_schema_check',  'schema_file', 'xxxx.avsc');
STORE avro INTO 'output' USING org.apache.pig.piggybank.storage.CSVExcelStorage(',');



No ";" or quotations required since it is a shell command.

Reference:
http://www.michael-noll.com/blog/2013/07/04/using-avro-in-mapreduce-jobs-with-hadoop-pig-hive/