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https://issues.apache.org/jira/browse/GOBBLIN-877?focusedWorklogId=309238&page=com.atlassian.jira.plugin.system.issuetabpanels:worklog-tabpanel#worklog-309238
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ASF GitHub Bot logged work on GOBBLIN-877:
------------------------------------------

                Author: ASF GitHub Bot
            Created on: 09/Sep/19 20:56
            Start Date: 09/Sep/19 20:56
    Worklog Time Spent: 10m 
      Work Description: ZihanLi58 commented on pull request #2731: 
[GOBBLIN-877]Add column metadata for partition for inline hive registration
URL: https://github.com/apache/incubator-gobblin/pull/2731
 
 
   
   Dear Gobblin maintainers,
   
   Please accept this PR. I understand that it will not be reviewed until I 
have checked off all the steps below!
   
   
   ### JIRA
   - [ ] My PR addresses the following [Gobblin 
JIRA](https://issues.apache.org/jira/browse/GOBBLIN/) issues and references 
them in the PR title. For example, "[GOBBLIN-XXX] My Gobblin PR"
       - https://issues.apache.org/jira/browse/GOBBLIN-877
   
   
   ### Description
   - [ ] Here are some details about my PR, including screenshots (if 
applicable):
   Previously, we remove the schema.literal for partition.  Because Avro 
schemas should only be defined at the table level. Hive overrides table 
properties if the same property is defined on the partition. Defining them at 
the partition level may lead to partitions with inconsistent schemas. And 
because column metadata is calculated from schema.literal, so we remove the 
column metadata as well.
   
   Then we encounter a problem that presto cannot read data from orc file. 
Because ORC (and other Hive serdes) need metadata in the partitions so that 
coercion can be done between a partition schema and the table schema.
   
   So we need to treat Avro and other formate separately to make sure hive 
registration works well so that user can read right data from Presto.
   
   ### Tests
   - [ ] My PR adds the following unit tests __OR__ does not need testing for 
this extremely good reason:
   Test on dataset written in orc format and I can read data from presto 
   
   ### Commits
   - [ ] My commits all reference JIRA issues in their subject lines, and I 
have squashed multiple commits if they address the same issue. In addition, my 
commits follow the guidelines from "[How to write a good git commit 
message](http://chris.beams.io/posts/git-commit/)":
       1. Subject is separated from body by a blank line
       2. Subject is limited to 50 characters
       3. Subject does not end with a period
       4. Subject uses the imperative mood ("add", not "adding")
       5. Body wraps at 72 characters
       6. Body explains "what" and "why", not "how"
   
   
 
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Issue Time Tracking
-------------------

            Worklog Id:     (was: 309238)
    Remaining Estimate: 0h
            Time Spent: 10m

> Add column metadata for partition for inline hive registration
> --------------------------------------------------------------
>
>                 Key: GOBBLIN-877
>                 URL: https://issues.apache.org/jira/browse/GOBBLIN-877
>             Project: Apache Gobblin
>          Issue Type: Task
>            Reporter: Zihan Li
>            Priority: Major
>          Time Spent: 10m
>  Remaining Estimate: 0h
>
> Previously, we remove the schema.literal for partition.  Because Avro schemas 
> should _only_ be defined at the table level. Hive overrides table properties 
> if the same property is defined on the partition. Defining them at the 
> partition level may lead to partitions with inconsistent schemas. And because 
> column metadata is calculated from schema.literal, so we remove the column 
> metadata as well.
> Then we encounter a problem that presto cannot read data from orc file. 
> Because ORC (and other Hive serdes) need metadata in the partitions so that 
> coercion can be done between a partition schema and the table schema.
> So we need to treat Avro and other formate separately to make sure hive 
> registration works well so that user can read right data from Presto.



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