Exam Certified Associate Developer for Apache Spark topic 1 question 134 discussion

Actual exam question from Databricks's Certified Associate Developer for Apache Spark

Question #: 134
Topic #: 1

[All Certified Associate Developer for Apache Spark Questions]

The code block shown below contains an error. The code block is intended to return a new DataFrame from DataFrame storesDF where column storeId is of the type string. Identify the error.

Code block:

storesDF.withColumn(“storeId”, cast(col(“storeId”), StringType()))

A. Calls to withColumn() cannot create a new column of the same name on which it is operating.
B. DataFrame columns cannot be converted to a new type inside of a call to withColumn().
C. The call to StringType should not be followed by parentheses.
D. The column name storeId inside the col() operation should not be quoted.
E. The cast() operation is a method in the Column class rather than a standalone function.