Upgrading from PySpark 2.3 to 2.4¶

In PySpark, when Arrow optimization is enabled, previously toPandas just failed when Arrow optimization is unable to be used whereas createDataFrame from Pandas DataFrame allowed the fallback to non-optimization. Now, both toPandas and createDataFrame from Pandas DataFrame allow the fallback by default, which can be switched off by spark.sql.execution.arrow.fallback.enabled.