[
https://issues.apache.org/jira/browse/SPARK-21582?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16107014#comment-16107014
]
Takeshi Yamamuro commented on SPARK-21582:
------------------------------------------
I feel making ~900 dataframes is heavy...
> DataFrame.withColumnRenamed cause huge performance overhead
> -----------------------------------------------------------
>
> Key: SPARK-21582
> URL: https://issues.apache.org/jira/browse/SPARK-21582
> Project: Spark
> Issue Type: Improvement
> Components: SQL
> Affects Versions: 2.1.0
> Reporter: GuangFancui(ISCAS)
> Attachments: 4654.stack
>
>
> Table "item_feature" (DataFrame) has over 900 columns.
> When I use
> {code:java}
> val nameSequeceExcept = Set("gid","category_name","merchant_id")
> val df1 = spark.table("item_feature")
> val newdf1 = df1.schema.map(_.name).filter(name =>
> !nameSequeceExcept.contains(name)).foldLeft(df1)((df1, name) =>
> df1.withColumnRenamed(name, name + "_1" ))
> {code}
> It took over 30 minutes.
> *PID* in stack file is *0x126d*
> It seems that _transform_ took too long time.
--
This message was sent by Atlassian JIRA
(v6.4.14#64029)
---------------------------------------------------------------------
To unsubscribe, e-mail: issues-unsubscr...@spark.apache.org
For additional commands, e-mail: issues-h...@spark.apache.org
