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https://issues.apache.org/jira/browse/TAJO-1359?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14532821#comment-14532821
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ASF GitHub Bot commented on TAJO-1359:
--------------------------------------

Github user jihoonson commented on a diff in the pull request:

    https://github.com/apache/tajo/pull/422#discussion_r29860469
  
    --- Diff: 
tajo-core/src/main/java/org/apache/tajo/engine/planner/physical/SeqScanExec.java
 ---
    @@ -186,6 +195,7 @@ private void initScanner(Schema projected) throws 
IOException {
         // set system default properties
         
PlannerUtil.applySystemDefaultToTableProperties(context.getQueryContext(), 
meta);
     
    +    // TODO - If fragments is null, we don't need to make any task. We 
should investigate it later
    --- End diff --
    
    How about logging a debug message for later investigation?


> Add nested field projector and language extension to project nested record
> --------------------------------------------------------------------------
>
>                 Key: TAJO-1359
>                 URL: https://issues.apache.org/jira/browse/TAJO-1359
>             Project: Tajo
>          Issue Type: Sub-task
>          Components: parser, physical operator, planner/optimizer
>            Reporter: Hyunsik Choi
>            Assignee: Hyunsik Choi
>             Fix For: 0.11.0
>
>         Attachments: TAJO-1359.patch, TAJO-1359_2.patch, TAJO-1359_3.patch, 
> TAJO-1359_4.patch, TAJO-1359_5.patch, TAJO-1359_6.patch, TAJO-1359_7.patch
>
>
> We need to improve Projector class to get nested record fields, and we also 
> add some language extension to specify certain nested records in table 
> schema. Both works should be done together. Otherwise, we need to test an 
> entire work process.
> Using dot '.' would be good for the syntax to specify nested fields. Many 
> systems (Hive, Google BigQuery, and Drill) already use this syntax. Probably, 
> many users are familiar with this form.
> For example, if *employee* is a root nested record field and it includes 
> *age* and *name* fields, consisting two fields lastname and firstname, we can 
> specify them individually as follows:
> {code}
> SELECT employee.age, employee.name.lastname, employee.name.firstname FROM ...
> {code}



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