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https://issues.apache.org/jira/browse/HIVE-2889?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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Ashutosh Chauhan updated HIVE-2889:
-----------------------------------

    Fix Version/s:     (was: 0.9.0)

Unlinking from 0.9 
                
> LOAD DATA IF NOT EXISTS functionality
> -------------------------------------
>
>                 Key: HIVE-2889
>                 URL: https://issues.apache.org/jira/browse/HIVE-2889
>             Project: Hive
>          Issue Type: Improvement
>          Components: Import/Export
>    Affects Versions: 0.8.1
>            Reporter: Sean McNamara
>
> *Background:*
> The behavior of LOAD DATA LOCAL INPATH has changed.  It used to give you an 
> error when trying to copy in a log that already existed.  Now it re-names the 
> file with copy_1 so the file always goes into hdfs.
> *Original discussion:*
> http://mail-archives.apache.org/mod_mbox/hive-user/201203.mbox/%3CCB8D2849.14F69%25sean.mcnamara%40webtrends.com%3E
> *Issue:*
> There is no longer an atomic way to insert files into hive and guarantee that 
> the file won't go in twice.  Using OVERWRITE will cause other logs in the 
> table/partition to be deleted.
> *Example:*
> {{/usr/local/hive/bin/hive -e "LOAD DATA LOCAL INPATH 'test_a.bz2' INTO TABLE 
> logs PARTITION(ds='2012-03-19', hr='23')"}}
> {{/usr/local/hive/bin/hive -e "LOAD DATA LOCAL INPATH 'test_b.bz2' INTO TABLE 
> logs PARTITION(ds='2012-03-19', hr='23')"}}
> {{/usr/local/hive/bin/hive -e "LOAD DATA LOCAL INPATH 'test_b.bz2' INTO TABLE 
> logs PARTITION(ds='2012-03-19', hr='23')"}}
> {{/usr/local/hive/bin/hive -e "LOAD DATA LOCAL INPATH 'test_b.bz2' INTO TABLE 
> logs PARTITION(ds='2012-03-19', hr='23')"}}
> *Result:*
> {{test_a.bz2}}
> {{test_b.bz2}}
> {{test_b_copy_1.bz2}}
> {{test_b_copy_2.bz2}}
> _test_b data was inserted 3 times, which is not the desired behavior in this 
> instance._
> *Proposal:*
> Add _IF NOT EXISTS_ flag to indicate copy semantics.  If the the log file 
> does not exist in the table/partition, the log would go in normally.  If the 
> log does exist in the table/partition hive would return an error and return 
> an exit code.
> *Proposed HiveQL Example:*
> {{LOAD DATA LOCAL IF NOT EXISTS INPATH 'test_a.bz2' INTO TABLE logs 
> PARTITION(ds='2012-03-19', hr='23')}}

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