无法使用 PySpark 与 Databricks 上的 apache spark function to_timestamp() 连接并添加一列

Question

I'm trying to using concatenate with the to_timestamp() on a Apache Spark table and add a columns using the.withColumn function but it won't work.

The code is as follows:

DIM_WORK_ORDER.withColumn("LAST_MODIFICATION_DT", to_timestamp(concat(col('LAST_MOD_DATE'), lit(' '), col('LAST_MOD_TIME')), 'yyyyMMdd HHmmss'))

The result I would expect to see is something like

LAST_MODIFICATION_DT | WORK_ORDER

However, I'm getting the following result:

Some data to work with:

WORK_ORDER LAST_MOD_TIME 10000008 null 11358186 142254 10000007 193402 10000009 null

Any thoughts?

Answer 1

As far as I know in Spark, dataframes are immutable. Hence, once you have created a dataframe, it can't change.

%python
import pyspark
from pyspark.sql.functions import *
df = spark.read.option("header","true").csv("<input file path>")
df1 = df.withColumn("LAST_MODIFICATION_DT", to_timestamp(concat(col('LAST_MOD_DATE'), lit(' '), col('LAST_MOD_TIME')), 'yyyyMMdd HHmmss'))
display(df1)

I am getting below output as expected. If this is not what you expect, please provide more info