Confluent Confluent Certified Developer CCDAK Questions & Answers

• Question 31:

  Your manager would like to have topic availability over consistency. Which setting do you need to change in order to enable that?

  A. compression.type

  B. unclean.leader.election.enable

  C. min.insync.replicas

  Correct Answer: B

  unclean.leader.election.enable=true allows non ISR replicas to become leader, ensuring availability but losing consistency as data loss will occur

• Question 32:

  A producer application in a developer machine was able to send messages to a Kafka topic. After copying the producer application into another developer's machine, the producer is able to connect to Kafka but unable to produce to the same Kafka topic because of an authorization issue. What is the likely issue?

  A. Broker configuration needs to be changed to allow a different producer

  B. You cannot copy a producer application from one machine to another

  C. The Kafka ACL does not allow another machine IP

  D. The Kafka Broker needs to be rebooted

  Correct Answer: C

  ACLs take "Host" as a parameter, which represents an IP. It can be * (all IP), or a specific IP. Here, it's a specific IP as moving a producer to a different machine breaks the consumer, so the ACL needs to be updated

• Question 33:

  What client protocol is supported for the schema registry? (select two)

  A. HTTP

  B. HTTPS

  C. JDBC

  D. Websocket

  E. SASL

  Correct Answer: AB

  clients can interact with the schema registry using the HTTP or HTTPS interface

• Question 34:

  Which is an optional field in an Avro record?

  A. doc

  B. name

  C. namespace

  D. fields

  Correct Answer: A

  doc represents optional description of message

• Question 35:

  Which of the following errors are retriable from a producer perspective? (select two)

  A. MESSAGE_TOO_LARGE

  B. INVALID_REQUIRED_ACKS

  C. NOT_ENOUGH_REPLICAS

  D. NOT_LEADER_FOR_PARTITION

  E. TOPIC_AUTHORIZATION_FAILED

  Correct Answer: CD

  Both of these are retriable errors, others non-retriable errors. See the full list of errors and their "retriable" status herehttps://kafka.apache.org/protocol#protocol_error_codes

• Question 36:

  Select the Kafka Streams joins that are always windowed joins.

  A. KStream-KStream join

  B. KTable-KTable join

  C. KStream-GlobalKTable

  D. KStream-KTable join

  Correct Answer: A

  Seehttps://docs.confluent.io/current/streams/developer-guide/dsl-api.html#joining

• Question 37:

  A consumer wants to read messages from partitions 0 and 1 of a topic topic1. Code snippet is shown

  below.

  consumer.subscribe(Arrays.asList("topic1"));

  List pc = new ArrayList<>();

  pc.add(new PartitionTopic("topic1", 0)); pc.add(new PartitionTopic("topic1", 1)); consumer.assign(pc);

  A. This works fine. subscribe() will subscribe to the topic and assign() will assign partitions to the consumer.

  B. Throws IllegalStateException

  Correct Answer: B

  subscribe() and assign() cannot be called by the same consumer, subscribe() is used to leverage the consumer group mechanism, while assign() is used to manually control partition assignment and reads assignment

• Question 38:

  In Kafka Streams, by what value are internal topics prefixed by?

  A. tasks-

  B. application.id

  C. group.id

  D. kafka-streams-

  Correct Answer: B

  In Kafka Streams, the application.id is also the underlying group.id for your consumers, and the prefix for all internal topics (repartition and state)

• Question 39:

  What Java library is KSQL based on?

  A. Kafka Streams

  B. REST Proxy

  C. Schema Registry

  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

• Question 40:

  We would like to be in an at-most once consuming scenario. Which offset commit strategy would you recommend?

  A. Commit the offsets on disk, after processing the data

  B. Do not commit any offsets and read from beginning

  C. Commit the offsets in Kafka, after processing the data

  D. Commit the offsets in Kafka, before processing the data

  Correct Answer: D

  Here, we must commit the offsets right after receiving a batch from a call to .poll()