The PySpark Tutorials offered by us are developed in such a way that the concepts and terminologies related to Apache Spark can be understood just only once and if you are a good learner you should not get a need to learn it or revise it again. But when it comes to the practical hands-on and coding level of exercises and assignments, then we would recommend you to practice regularly so as not to lose the touch and be in the flow of Pyspark. This way you will be always market ready and ready to compete in the market.