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https://issues.apache.org/jira/browse/SPARK-24900?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16554094#comment-16554094
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Apache Spark commented on SPARK-24900:
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User 'sddyljsx' has created a pull request for this issue:
https://github.com/apache/spark/pull/21859
> speed up sort when the dataset is small
> ---------------------------------------
>
> Key: SPARK-24900
> URL: https://issues.apache.org/jira/browse/SPARK-24900
> Project: Spark
> Issue Type: Improvement
> Components: SQL
> Affects Versions: 2.3.1
> Reporter: SongXun
> Priority: Minor
> Labels: pull-request-available
> Original Estimate: 1h
> Remaining Estimate: 1h
>
> when running the sql like 'select * from order where order_status = 4 order
> by order_id', the pysical plan is:
> !https://ws1.sinaimg.cn/large/006tNc79ly1ftl01gtso1j31kw0ag43q.jpg!
> the Exchange rangepartitioning has two steps:
> 1. sample the rdd and get the RangePartitioner which has a rangeBounds
> !https://ws1.sinaimg.cn/large/006tNc79ly1ftl0a6ziytj30le0su0vw.jpg!
> 2. get the rddWithPartitionIds depending on the rangeBounds, and do the
> shuffle
> !https://ws1.sinaimg.cn/large/006tNc79ly1ftl0bapn6mj30l40ke769.jpg!
> !https://ws1.sinaimg.cn/large/006tNc79ly1ftl0brnj3jj30kq0mu40q.jpg!
> The filescan and filter will be executed twice, it may take a long time. If
> the final dataset is small, and the sample data covers all the data, there is
> no need to do so.
> !https://ws3.sinaimg.cn/large/006tNc79ly1ftl3u0091wj31600a8wh1.jpg!
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