[ 
https://issues.apache.org/jira/browse/SPARK-20144?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15951095#comment-15951095
 ] 

Sean Owen commented on SPARK-20144:
-----------------------------------

Probably best to wait for an informed opinion but I would assume for now you 
need to sort. 

I'm just saying that theoretically sorted data needs no data movement to become 
sorted because it is already. It may not actually even be expensive

> spark.read.parquet no long maintains ordering of the data
> ---------------------------------------------------------
>
>                 Key: SPARK-20144
>                 URL: https://issues.apache.org/jira/browse/SPARK-20144
>             Project: Spark
>          Issue Type: Bug
>          Components: SQL
>    Affects Versions: 2.0.2
>            Reporter: Li Jin
>
> Hi, We are trying to upgrade Spark from 1.6.3 to 2.0.2. One issue we found is 
> when we read parquet files in 2.0.2, the ordering of rows in the resulting 
> dataframe is not the same as the ordering of rows in the dataframe that the 
> parquet file was reproduced with. 
> This is because FileSourceStrategy.scala combines the parquet files into 
> fewer partitions and also reordered them. This breaks our workflows because 
> they assume the ordering of the data. 
> Is this considered a bug? Also FileSourceStrategy and FileSourceScanExec 
> changed quite a bit from 2.0.2 to 2.1, so not sure if this is an issue with 
> 2.1.



--
This message was sent by Atlassian JIRA
(v6.3.15#6346)

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

Reply via email to