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https://issues.apache.org/jira/browse/DRILL-982?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14100843#comment-14100843
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Jason Altekruse commented on DRILL-982:
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https://reviews.apache.org/r/24759/
> Parquet reader should return NULL value for non-exist column in execution
> phase, in stead of raising ExecutionSetupException
> ----------------------------------------------------------------------------------------------------------------------------
>
> Key: DRILL-982
> URL: https://issues.apache.org/jira/browse/DRILL-982
> Project: Apache Drill
> Issue Type: Bug
> Components: Storage - Parquet
> Reporter: Jinfeng Ni
> Assignee: Jason Altekruse
> Fix For: 0.5.0
>
> Attachments:
> 0001-DRILL-982-Return-nulls-for-non-existent-columns-in-p.patch
>
>
> If query a non-exist column against a parquet file, DRILL currently raises
> ExecutionSetupException:
> SELECT NON_EXIT_COLUMN from cp.`tpch/nation.parquet`;
> This will cause problem, when we have multiple parquet files, and the first
> one does not have the column, while the rest of them have the column.
>
> It would be better to return NULL expression during execution stage, if the
> columns does not exist in the parquet file.
> Later on, if DRILL adds a new option to verify column existence before
> executing a query ( just like what a schema-based system will do), we could
> throw PlanException in planning phase, once the parquet footer information is
> available to planner.
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