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https://issues.apache.org/jira/browse/SPARK-59396?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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XiDuo You updated SPARK-59396:
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    Summary: Enable SPJ partition filtering and ordering over partition keys by 
default  (was: Enable storage-partition join partition filtering and key 
ordering by default)

> Enable SPJ partition filtering and ordering over partition keys by default
> --------------------------------------------------------------------------
>
>                 Key: SPARK-59396
>                 URL: https://issues.apache.org/jira/browse/SPARK-59396
>             Project: Spark
>          Issue Type: Improvement
>          Components: SQL
>    Affects Versions: 5.0.0
>            Reporter: XiDuo You
>            Priority: Major
>
> Several Storage Partition Join (SPJ) configurations stay opt-in even though 
> enabling them only removes work. This issue proposes turning three of them on 
> by default:
> - spark.sql.sources.v2.bucketing.partition.filter.enabled: the partition key 
> groups pushed down to both join sides are narrowed to those that can produce 
> output for the join type, so a group that cannot match is never scanned 
> instead of being padded with an empty partition.
> - spark.sql.sources.v2.bucketing.partitionKeyOrdering.enabled: a V2 scan that 
> reports a keyed partitioning but no explicit ordering is trivially sorted by 
> its partition key expressions, so a Sort above the scan is redundant.
> - spark.sql.sources.v2.bucketing.preserveKeyOrderingOnCoalesce.enabled: 
> GroupPartitionsExec keeps sort orders over partition key expressions when 
> merging partitions that share one key value, because those expressions are 
> constant within the merged partition.
> None of the three adds work, depends on table statistics, or changes query 
> results: the first scans a strict subset of what it scans today, and the 
> other two report orderings that already hold, which lets Spark drop sorts it 
> would otherwise add. The remaining SPJ flags keep their current default, 
> since those trade shuffle elimination for data skew, extra per-row cost, or 
> extra memory.



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