Cassandra has Pig support for loading and storing starting with Cassandra 0.7. It requires Pig 0.7+. The CassandraStorage class (for loading and storing) is found in the Cassandra src and it's currently in a contrib module (http://cassandra.apache.org/download/Image Removed). Details are found in the readme there. More hadoop support details are found here: http://wiki.apache.org/cassandra/HadoopSupportImage Removed. A project that looks to ease integration between the two is Pygmalion: https://github.com/jeromatron/pygmalion/Image Removed.
Pig and HBase
In Pig 0.6 and before, the built in HBaseStorage can be used to load data from Hbase. Work is ongoing to enhance this loader and make it a storage function also. See http://issues.apache.org/jira/browse/PIG-1205Image Removed
Pig and Hive RCFiles
The Pig LoadFunc for Voldemort.
See http://github.com/rsumbaly/voldemort/blob/hadoop/contrib/hadoop/src/java/voldemort/hadoop/pig/VoldemortStore.javaImage Removed