Databricks Certified Associate Developer for Apache Spark — Question 74

Which of the following code blocks returns a new DataFrame with a new column customerSatisfactionAbs that is the absolute value of column customerSatisfaction in DataFrame storesDF? Note that column customerSatisfactionAbs is not in the original DataFrame storesDF.

Answer options

• A. storesDF.withColumn(“customerSatisfactionAbs”, abs(col(“customerSatisfaction”)))
• B. storesDF.withColumnRenamed(“customerSatisfactionAbs”, abs(col(“customerSatisfaction”)))
• C. storesDF.withColumn(col(“customerSatisfactionAbs”, abs(col(“customerSatisfaction”)))
• D. storesDF.withColumn(“customerSatisfactionAbs”, abs(col(customerSatisfaction)))
• E. storesDF.withColumn(“customerSatisfactionAbs”, abs(“customerSatisfaction”))

Correct answer: A

Explanation

Option A is correct because it properly uses the withColumn method to add a new column named customerSatisfactionAbs, where the absolute value of customerSatisfaction is calculated. Option B incorrectly attempts to rename a column that does not exist. Option C has a syntax error by missing a closing parenthesis. Option D incorrectly uses col() without quotes around the column name, which will cause an error. Option E uses the abs function incorrectly by passing a string instead of a column reference.