When you join tables which are distributed on the same key and used these key columns in the join condition, then each SPU (machine) in netezza works 100% independent of the other (see nz-interview<http://www.folkstalk.com/2011/06/netezza-interview-questions-part-2.html> ).
In hive, there's bucketed map join<https://issues.apache.org/jira/browse/HIVE-917>, but the distribution of the files representing the tables to datanode is the responsibility of HDFS, it's not done according to hive CLUSTERED BY key! so suppose I have 2 tables, CLUSTERED BY the same key, and I join by that key - can hive get a guarantee from HDFS that matching buckets will sit on the same node? or will it always have to move the matching bucket of the small table to the datanode containing the big table bucket? Thanks, ido (Resend, since my last mail didn't reach the list)
