NameError: name 'col' is not defined

Maser_AZ — Wed, 21 Aug 2019 22:15:22 GMT

I m executing the below code and using Pyhton in notebook and it appears that the col() function is not getting recognized .

I want to know if the col() function belongs to any specific Dataframe library or Python library .I dont want to use pyspark api and would like to write code using sql dataframes API

Trying to run the below code and getting error -NameError: name 'col' is not defined

peopleDF = spark.read.parquet("/mnt/training/dataframes/people-10m.parquet") peopleDF.printSchema() peopleDF.show() peopleDF.select(col("firstName")).filter(col("firstName"))=="An"

As per SPARK doc

https://spark.apache.org/docs/latest/api/scala/index.html#org.apache.spark.sql.Column

df("columnName")            // On a specific `df` DataFrame.
col("columnName")           // A generic column not yet associated with a DataFrame.
col("columnName.field")     // Extracting a struct field
col("`a.column.with.dots`") // Escape `.` in column names.
$"columnName"               // Scala short hand for a named column.

Re: NameError: name 'col' is not defined

MOHAN_KUMARL_N — Thu, 22 Aug 2019 09:18:12 GMT

@mudassar45@gmail.com

as the document describe generic column not yet associated. Please refer the below code.

display(peopleDF.select("firstName").filter("firstName = 'An'"))

topic Re: NameError: name 'col' is not defined in Data Engineering

NameError: name 'col' is not defined

Re: NameError: name 'col' is not defined