[jira] [Created] (SPARK-34980) Support coalesce partition through union

["ulysses you (Jira)" <ji...@apache.org>]

ulysses you created SPARK-34980:
-----------------------------------

             Summary: Support coalesce partition through union
                 Key: SPARK-34980
                 URL: https://issues.apache.org/jira/browse/SPARK-34980
             Project: Spark
          Issue Type: Improvement
          Components: SQL
    Affects Versions: 3.2.0
            Reporter: ulysses you


The rule `CoalesceShufflePartitions` can only coalesce paritition if
* leaf node is ShuffleQueryStage
* all shuffle have same partition number

With `Union`, it might break the assumption. Let's say we have such plan
{code:java}
Union
   HashAggregate
      ShuffleQueryStage
   FileScan
{code}

`CoalesceShufflePartitions` can not optimize it and the result partition would be `shuffle partition + FileScan partition` which can be quite lagre.

It's better to support partial optimize with `Union`.



--
This message was sent by Atlassian Jira
(v8.3.4#803005)

---------------------------------------------------------------------
To unsubscribe, e-mail: issues-unsubscribe@spark.apache.org
For additional commands, e-mail: issues-help@spark.apache.org