topic Re: Differences between lit(None) or lit(None).cast('string') in Data Engineering

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

SaraCorralLou — Tue, 07 Feb 2023 14:29:21 GMT

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?

Can both be used? Is there a wrong one?

Thank you so much!

Murthy1 — Tue, 07 Feb 2023 16:06:47 GMT

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 — Sat, 08 Apr 2023 07:22:39 GMT

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shadowinc — Fri, 31 Jan 2025 12:33:37 GMT

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))