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https://issues.apache.org/jira/browse/TAJO-1426?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14372806#comment-14372806
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ASF GitHub Bot commented on TAJO-1426:
--------------------------------------

Github user jihoonson commented on the pull request:

    https://github.com/apache/tajo/pull/441#issuecomment-84362382
  
    @navis thanks for your work. This will be definitely useful. 
    However, it seems that the title sould be changed. I think that you already 
know, but would like to explain for clarity. 
    In Tajo, there are three planning phases, i.e., logical planning phase, 
global planning phase, and physical planning phase. When a query is submitted, 
the logical planner generates a logical plan based on the query. And then, the 
global planner generates a master plan that explains how the query is executed 
in distributed manner. Once the master plan is generated, the query master 
executes execution blocks of that master plan subsequently. 
    An execution block is executed by multiple workers. For distributed 
execution, each worker receives the logical plan corresponds to the currently 
executing execution block. Finally, a worker generates a physical plan based on 
the received logical plan. It indicates which types of physical operators are 
used to execute the logical plan. For example, given a logical plan for join, 
the physical plan indicates that the hash join or sorted-merge join will be 
used. 
    Your work seems to see the the master (global) plan. So, it would be better 
to change the title. 
    
    Anyway, I'm still reviewing. I'll finish soon. 


> Support "explain physical" to get physical plan
> -----------------------------------------------
>
>                 Key: TAJO-1426
>                 URL: https://issues.apache.org/jira/browse/TAJO-1426
>             Project: Tajo
>          Issue Type: Improvement
>            Reporter: Navis
>            Assignee: Navis
>            Priority: Minor
>
> Inconvenient to see that in log file.



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