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https://issues.apache.org/jira/browse/TAJO-744?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13974936#comment-13974936
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Alvin Henrick commented on TAJO-744:
------------------------------------

Hi Hyunsik , You don't sleep . It's 4 A.M. in South Korea I guess :) ...Hmm so 
my thought process for DROP was right .Got it. It will help user to drop 
multiple partitions. I will read JIRA-711 to understand the WITH clause better.

Thanks!
Warm Regards,
Alvin.



> ALTER TABLE ADD/DROP PARTITION statement
> ----------------------------------------
>
>                 Key: TAJO-744
>                 URL: https://issues.apache.org/jira/browse/TAJO-744
>             Project: Tajo
>          Issue Type: New Feature
>          Components: catalog
>    Affects Versions: 0.9
>            Reporter: Hyunsik Choi
>            Assignee: Alvin Henrick
>             Fix For: 0.9
>
>
> Currently, Tajo does not manage partitioned directly. In Tajo, each partition 
> is just a directory. For each query, a logical planner traverses matched 
> directories in HDFS according to partition predicates.
> This approach is not efficient especially in the environment where the number 
> of partitions are very large. It also makes partition management hard.
> Tajo should manage partitions directly by using ALTER TABLE ADD/DROP 
> PARTITION statements. A number of partition entries should be stored in the 
> underlying database that catalog uses.
> {code:title=Synopsis of ALTER TABLE ADD/DROP PARTITION}
> ALTER TABLE table_name [IF NOT EXISTS] ADD COLUMN PARTITION (key1 = 'val2', 
> key2 = 'val2', ...) WITH ('prop_key' = 'prop_val', ...) LOCATION '...';
> ALTER TABLE table_name [IF EXISTS] DROP COLUMN PARTITION  (key1 
> [=|<|<=|>|>=|!=] 'val1');
> {code}



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