Exam Certified Associate Developer for Apache Spark topic 1 question 56 discussion

C is correct according to documentation: https://spark.apache.org/docs/3.1.1/api/python/reference/api/pyspark.sql.DataFrame.unionByName.html "The difference between this function and union() is that this function resolves columns by name (not by position)"

C is correct - https://spark.apache.org/docs/3.1.1/api/python/reference/api/pyspark.sql.DataFrame.unionByName.html

The error in the code block is: C. The DataFrame.unionByName() operation does not union DataFrames based on column position – it uses column name instead. The unionByName() operation performs a position-wise union based on column names, not based on column positions. Therefore, the error in the code block is that the intended operation should be union(), which performs a position-wise union regardless of column names. The correct code block to perform a position-wise union between DataFrame storesDF and DataFrame acquiredStoresDF would be: storesDF.union(acquiredStoresDF)