Daniel Dai created HIVE-17421:
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             Summary: Clear incorrect stats after replication
                 Key: HIVE-17421
                 URL: https://issues.apache.org/jira/browse/HIVE-17421
             Project: Hive
          Issue Type: Bug
          Components: repl
            Reporter: Daniel Dai
            Assignee: Daniel Dai


After replication, some stats summary are incorrect. If 
hive.compute.query.using.stats set to true, we will get wrong result on the 
destination side.

This will not happen with bootstrap replication. This is because stats summary 
are in table properties and will be replicated to the destination. However, in 
incremental replication, this won't work. When creating table, the stats 
summary are empty (eg, numRows=0). Later when we insert data, stats summary are 
updated with update_table_column_statistics/update_partition_column_statistics, 
however, both events are not captured in incremental replication. Thus on the 
destination side, we will get count(*)=0. The simple solution is to remove 
COLUMN_STATS_ACCURATE property after incremental replication.



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