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https://issues.apache.org/jira/browse/SPARK-17878?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15567104#comment-15567104
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Hossein Falaki commented on SPARK-17878:
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That would require API change in SparkSQL. Otherwise, we need to split the 
string passed to {{nullValue}} on a delimiter. Neither these are safe choices. 
I think accepting {{nullValue1}}, {{nullValue2}}, etc (along with existing 
{{nullValue}}) is:
* backwards compatible
* clear
* extensible for other options in future. E.g., quoteCharacter, etc.

> Support for multiple null values when reading CSV data
> ------------------------------------------------------
>
>                 Key: SPARK-17878
>                 URL: https://issues.apache.org/jira/browse/SPARK-17878
>             Project: Spark
>          Issue Type: Story
>          Components: SQL
>    Affects Versions: 2.0.1
>            Reporter: Hossein Falaki
>
> There are CSV files out there with multiple values that are supposed to be 
> interpreted as null. As a result, multiple spark users have asked for this 
> feature built into the CSV data source. It can be easily implemented in a 
> backwards compatible way:
> - Currently CSV data source supports an option named {{nullValue}}.
> - We can add logic in {{CSVOptions}} to understands option names that match 
> {{nullValue[\d]}}. This way user can specify a query with multiple or one 
> null value.
> {code}
> val df = spark.read.format("CSV").option("nullValue1", 
> "-").option("nullValue2", "*")....
> {code}



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