GitHub user prasanthj opened a pull request:

    https://github.com/apache/orc/pull/87

    ORC-135: PPD for timestamp is wrong when reader and writer timezones are 
different

    When reader and writer timezones are different, PPD evaluation does not 
offset the timezone when reading the min and max values. This can result is 
wrong PPD evaluation and hence incorrect results.
    
    Example:
    Table written in US/Eastern timezone. All values in this table are 
"2007-08-01 00:00:00.0".
    **PPD disabled**
    ```
    hive> set hive.optimize.index.filter=false;
    hive> select ORDER_DATE from ORDER_FACT_small where ORDER_DATE='2007-08-01 
00:00:00.0' limit 1;
    2007-08-01 00:00:00.0
    OK
    ```
    
    **PPD enabled**
    ```
    set hive.optimize.index.filter=true;
    select ORDER_DATE from ORDER_FACT_small where ORDER_DATE='2007-08-01 
00:00:00.0' limit 1;
    OK
    ```
    No rows are returned when PPD is enabled (reader timezone is UTC)

You can merge this pull request into a Git repository by running:

    $ git pull https://github.com/prasanthj/orc ORC-135

Alternatively you can review and apply these changes as the patch at:

    https://github.com/apache/orc/pull/87.patch

To close this pull request, make a commit to your master/trunk branch
with (at least) the following in the commit message:

    This closes #87
    
----
commit 5adda854d749afd773e1fb4e8002eafd6561d4f6
Author: Prasanth Jayachandran <[email protected]>
Date:   2017-01-27T01:48:25Z

    ORC-135: PPD for timestamp is wrong when reader and writer timezones are 
different

----


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