HIVE-1228 just got committed, which adds support for explicitly mapping any HIve column to the HBase row key.
Previously, the first HIve column was always implicitly mapped to the row key. In the future, support for the implicit mapping will be dropped (resulting in a CREATE TABLE exception if you omit :key), so if you're using the HBase integration, please adjust your DDL accordingly after you pick up HIVE-1228. I have updated the HBase storage handler spec and examples accordingly: http://wiki.apache.org/hadoop/Hive/HBaseIntegration#Column_Mapping JVS
