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https://issues.apache.org/jira/browse/HIVE-17714?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16193642#comment-16193642
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Sergey Shelukhin commented on HIVE-17714:
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cc [~alangates]

> move custom SerDe schema considerations into metastore from QL
> --------------------------------------------------------------
>
>                 Key: HIVE-17714
>                 URL: https://issues.apache.org/jira/browse/HIVE-17714
>             Project: Hive
>          Issue Type: Bug
>            Reporter: Sergey Shelukhin
>            Assignee: Alan Gates
>
> Columns in metastore for tables that use external schema don't have the type 
> information (since HIVE-11985) and may be entirely inconsistent (since 
> forever, due to issues like HIVE-17713; or for SerDes that allow an URL for 
> the schema, due to the change in the underlying file).
> Currently, if you trace the usage of ConfVars.SERDESUSINGMETASTOREFORSCHEMA, 
> and to MetaStoreUtils.getFieldsFromDeserializer, you'd see that the code in 
> QL handles this in Hive. So, for the most part metastore just returns 
> whatever is stored for columns in the database.
> One exception appears to be get_fields_with_environment_context, which is 
> interesting... so getTable will return incorrect columns (potentially), but 
> get_fields/get_schema will return correct ones from SerDe as far as I can 
> tell.
> As part of separating the metastore, we should make sure all the APIs return 
> the correct schema for the columns; it's not a good idea to have everyone 
> reimplement getFieldsFromDeserializer.



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