You are viewing a plain text version of this content. The canonical link for it is here.
Posted to issues@spark.apache.org by "Ankit Raj Boudh (Jira)" <ji...@apache.org> on 2020/05/08 09:52:00 UTC
[jira] [Commented] (SPARK-31657) CSV Writer writes no header for
empty DataFrames
[ https://issues.apache.org/jira/browse/SPARK-31657?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17102420#comment-17102420 ]
Ankit Raj Boudh commented on SPARK-31657:
-----------------------------------------
[~fpin], I will raise PR for this
> CSV Writer writes no header for empty DataFrames
> ------------------------------------------------
>
> Key: SPARK-31657
> URL: https://issues.apache.org/jira/browse/SPARK-31657
> Project: Spark
> Issue Type: Bug
> Components: Input/Output
> Affects Versions: 2.4.1
> Environment: Local pyspark 2.41
> Reporter: Furcy Pin
> Priority: Minor
>
> When writing a DataFrame as csv with the Header option set to true,
> the header is not written when the DataFrame is empty.
> This creates failures for processes that read the csv back.
> Example (please notice the limit(0) in the second example):
> ```
>
> {code:java}
> Welcome to
> ____ __
> / __/__ ___ _____/ /__
> _\ \/ _ \/ _ `/ __/ '_/
> /__ / .__/\_,_/_/ /_/\_\ version 2.4.1
> /_/
> Using Python version 2.7.17 (default, Nov 7 2019 10:07:09)
> SparkSession available as 'spark'.
> >>> df1 = spark.sql("SELECT 1 as a")
> >>> df1.limit(1).write.mode("OVERWRITE").option("Header", True).csv("data/test/csv")
> >>> spark.read.option("Header", True).csv("data/test/csv").show()
> +---+
> | a|
> +---+
> | 1|
> +---+
> >>>
> >>> df1.limit(0).write.mode("OVERWRITE").option("Header", True).csv("data/test/csv")
> >>> spark.read.option("Header", True).csv("data/test/csv").show()
> ++
> ||
> ++
> ++
> {code}
>
> Expected behavior:
> {code:java}
> >>> df1.limit(0).write.mode("OVERWRITE").option("Header", True).csv("data/test/csv")
> >>> spark.read.option("Header", True).csv("data/test/csv").show()
> +---+
> | a|
> +---+
> +---+{code}
--
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