In Avro, removing a field that does not have a default is a schema evolution

1. A. breaking
2. B. full
3. C. backward
4. D. forward

Correct Answer: C
Clients with new schema will be able to read records saved with old schema.

What is the disadvantage of request/response communication?

1. A. Scalability
2. B. Reliability
3. C. Coupling
4. D. Cost

Correct Answer: C
Point-to-point (request-response) style will couple client to the server.

Where are the ACLs stored in a Kafka cluster by default?

1. A. Inside the broker's data directory
2. B. Under Zookeeper node /kafka-acl/
3. C. In Kafka topic kafka_acls
4. D. Inside the Zookeeper's data directory

Correct Answer: A
ACLs are stored in Zookeeper node /kafka-acls/ by default.

What Java library is KSQL based on?

1. A. Kafka Streams
2. B. REST Proxy
3. C. Schema Registry
4. D. Kafka Connect

Correct Answer: A
KSQL is based on Kafka Streams and allows you to express transformations in the SQL language that get automatically converted to a Kafka Streams program in the backend

Which KSQL queries write to Kafka?

1. A. COUNT and JOIN
2. B. SHOW STREAMS and EXPLAIN <query> statements
3. C. CREATE STREAM WITH <topic> and CREATE TABLE WITH <topic>
4. D. CREATE STREAM AS SELECT and CREATE TABLE AS SELECT

Correct Answer: CD
SHOW STREAMS and EXPLAIN <query> statements run against the KSQL server that the KSQL client is connected to. They don't communicate directly with Kafka. CREATE STREAM WITH <topic> and CREATE TABLE WITH <topic> write metadata to the KSQL command topic. Persistent queries based on CREATE STREAM AS SELECT and CREATE TABLE AS SELECT read and write to Kafka topics. Non-persistent queries based on SELECT that are stateless only read from Kafka topics, for example SELECT … FROM foo WHERE …. Non-persistent queries that are stateful read and write to Kafka, for example, COUNT and JOIN. The data in Kafka is deleted automatically when you terminate the query with CTRL-C.