title: Kafka Avro Schema evolution
body: <p>I am trying to learn more about the Avro schemas which we use for our Kafka topics and I am relatively new to this. </p>
  
  <p>I was wondering is there a way to evolve schemas in a particular situation. We update our schema with a new field that can't be null or any default values because these new fields are identifiers. The workaround to solve this is to create new topics, but is there a better way to evolve existing schemas?</p>