pengcheng xiong created HIVE-7506:
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             Summary: MetadataUpdater: provide a mechanism to edit the 
statistics of a column in a table (or a partition of a table)
                 Key: HIVE-7506
                 URL: https://issues.apache.org/jira/browse/HIVE-7506
             Project: Hive
          Issue Type: New Feature
          Components: Database/Schema
            Reporter: pengcheng xiong
            Assignee: pengcheng xiong
            Priority: Critical


Two motivations:

(1) CBO depends heavily on the statistics of a column in a table (or a 
partition of a table). If we would like to test whether CBO chooses the best 
plan under different statistics, it would be time consuming if we load the 
whole table and create the statistics from ground up.

(2) As database runs,  the statistics of a column in a table (or a partition of 
a table) may change. We need a way or a mechanism to synchronize. 

We propose the following command to achieve that:

ALTER TABLE table_name PARTITION partition_spec COLUMN col_name UPDATE 
STATISTICS col_statistics [COMMENT col_comment]






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