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https://issues.apache.org/jira/browse/SPARK-59595?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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ASF GitHub Bot updated SPARK-59595:
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    Labels: pull-request-available  (was: )

> Data source expression normalization scales poorly for wide schemas
> -------------------------------------------------------------------
>
>                 Key: SPARK-59595
>                 URL: https://issues.apache.org/jira/browse/SPARK-59595
>             Project: Spark
>          Issue Type: Improvement
>          Components: SQL
>    Affects Versions: 4.2.0
>            Reporter: Ben Hollis
>            Priority: Minor
>              Labels: pull-request-available
>
> DataSourceStrategy.normalizeExprs searches the relation output for every 
> attribute reference being normalized. Its runtime is proportional to the 
> number of output attributes multiplied by the number of references. This 
> causes substantial planning overhead for wide schemas and projections. A 
> local benchmark with 10,000 attributes and 10,000 references took 
> approximately 876 ms per call. The method may also be called several times 
> per scan during optimization and physical planning.



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