Differences between lit(None) or lit(None).cast('string')

[SaraCorralLou]

I want to define a column with null values in my dataframe using pyspark. This column will later be used for other calculations.

What is the difference between creating it in these two different ways?

• df.withColumn("New_Column", lit(None))
• df.withColumn("New_Column", lit(None).cast('string'))

Can both be used? Is there a wrong one?

Thank you so much!

[Murthy1 · Accepted solution]

Hello!

An elegant way of defining an empty column in a dataframe is to mention as

df.withColumn("New_Column", lit(None).cast(StringType()))

If you are just working with dataframes ( and no file formats are involved) you can also work with NullType().

[Anonymous]

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[shadowinc]

For me 

df.withColumn("New_Column", lit(None).cast(StringType()))

this didn't work.

I used this instead

df.withColumn("New_Column", lit(null).cast(StringType))