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A normal skewed table can be used for skewed join, etc. (See the Skewed Join Optimization design document.) You don't need to define it as a list bucketing table if you don't use the list bucketing feature.

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Alter table <T> partition <P> concatenate; needs to be changed to merge files per directory.

Implementation

HIVE-3026 is the root JIRA ticket for the list bucketing feature.  It has links to additional JIRA tickets which implement list bucketing in Hive, including: 

• HIVE-3554:  Hive List Bucketing – Query logic (release 0.10.0)
• HIVE-3649:  Hive List Bucketing - enhance DDL to specify list bucketing table (release 0.10.0)
• HIVE-3072:  Hive List Bucketing - DDL support (release 0.10.0)
• HIVE-3073:  Hive List Bucketing - DML support (release 0.11.0)

For more information, see Skewed Tables in the DDL document.