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https://issues.apache.org/jira/browse/SPARK-36858?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17421935#comment-17421935
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Hyukjin Kwon commented on SPARK-36858:
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Can't we simply do this in a for loop?
> Spark API to apply same function to multiple columns
> ----------------------------------------------------
>
> Key: SPARK-36858
> URL: https://issues.apache.org/jira/browse/SPARK-36858
> Project: Spark
> Issue Type: New Feature
> Components: Spark Core
> Affects Versions: 2.4.8, 3.1.2
> Reporter: Armand BERGES
> Priority: Minor
>
> Hi
> My team and I have regularly need to apply the same function to multiple
> columns at once.
> For example, we want to remove all non alphanumerical characters to each
> columns of our dataframes.
> When we hit this use case first, some people in my team were using this kind
> of code :
> {code:java}
> val colListToClean = .... ## Generate some list, could be very long.
> val dfToClean: DataFrame = ... ## This is the dataframe we want to clean
> def cleanFunction(colName: String): Column = ... ## Write some function to
> manipulate column based on its name.
> val dfCleaned = colListToClean.foldLeft(dfToClean)((df, colName) =>
> df.withColumn(colName, cleanFunction(colName)){code}
> This kind of code when applied on a large set of columns overloaded our
> driver (because a Dataframe is generated for each column to clean).
> Based on this issue, we developed some code to add two functions :
> * One to apply the same function to multiple columns
> * One to rename multiple columns based on a Map.
>
> I wonder if your ever ask your team to add such kind of API ? If you did, had
> you any kind of issue regarding the implementation ? If you didn't, is this
> any idea you could add to Spark ?
> Best regards,
>
> LvffY
>
>
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