You can change schemas stored in the Confluent Schema Registry, it’s just that the default config enforces backward compatibility. You can change that compatibility config using the following parameter:
avro.compatibility.level
The Avro compatibility type. Valid values are:
none
(new schema can be any valid Avro schema),
backward
(new schema can read data produced by latest registered schema),
backward_transitive
(new schema can read data produced by all previously registered schemas),
forward
(latest registered schema can read data produced by the new schema),
forward_transitive
(all previously registered schemas can read data produced by the new schema),
full
(new schema is backward and forward compatible with latest registered schema),
full_transitive
(new schema is backward and forward compatible with all previously registered schemas)
Type: string Default: “backward” Importance: high