schemaId 
  This is a wrapper structure to contain schema identity fields. The structure contains:
- SchemaId$SchemaArn: The Amazon Resource Name (ARN) of the schema. Either - SchemaArnor- SchemaNameand- RegistryNamehas to be provided.
- SchemaId$SchemaName: The name of the schema. Either - SchemaArnor- SchemaNameand- RegistryNamehas to be provided.