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https://issues.apache.org/jira/browse/TAJO-1359?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14370519#comment-14370519
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ASF GitHub Bot commented on TAJO-1359:
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Github user hyunsik commented on the pull request:
https://github.com/apache/tajo/pull/422#issuecomment-83844491
Hi @jihoonson,
> It looks that a record column and a table have the same name. In this
case, how can we identify them exactly?
Here is how to resolve names.
https://github.com/apache/tajo/pull/422/files#diff-23481c6f9849708ac4a57d2252714846R312
There is a priority about resolving names. If a record column and a table,
a table has a higher priority. To resolve this problem, users should use full
qualified names.
Could you explain what alias for nested record is? Is it different from
just column alias?
> 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
>
>
> 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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