Please download latest SparkJDBC42.jar file from below URL and place the file in erwin Data Modeler 12.1 install directory and usage.
erwin Data Modeler Install Directory: C:\Program Files\erwin\Data Modeler r9\JDBC_JAR\SparkJDBC42.jar
Extract SimbaSparkJDBC42-2.6.22.1040.zip and then copy SparkJDBC42.jar and replace file in to erwin Data Modeler Install Directory folder: C:\Program Files\erwin\Data Modeler r9\JDBC_JAR\SparkJDBC42.jar