CCDAK Exam Dumps : Confluent Certified Developer for Apache Kafka Certification Examination

Kafka Streams usestransactional producersto guaranteeexactly-once semantics (EOS). This ensures that both theoutput recordsandstate store updatesare committed atomically, avoiding duplication or partial writes.

FromKafka Streams Documentation > Processing Guarantees:

“Kafka Streams leveragesKafka’s transactional APIsto commit the output records and internal state updatesas a single atomic unit, thereby providing exactly-once semantics.”

Option A is incorrect because log compaction is not disabled for EOS.

Option C incorrectly describes a checkpointing system Kafka Streams does not use.

Option D refers to deduplication, which is not how EOS is achieved in Streams.

RetriableException is a subclass of KafkaException, indicating transient issues thatmight succeed if retried. Examples include:

LeaderNotAvailableException: Happens when metadata is not yet propagated or leader election is in progress.

NotEnoughReplicasException: Happens when the number of in-sync replicas is insufficient. This can be transient if replicas come back online.

From theApache Kafka Java Client documentation:

"These exceptions (like LeaderNotAvailableException, NotEnoughReplicasException) are transient and the client will retry them automatically depending on retry configuration."

RecordTooLargeExceptionandAuthorizationExceptionarenon-retriableas they indicate client-side or permission errors.

Increasing partitions increasesparallelism, but also means:

Consumers in a group may have to handlemore partitions, especially if the number of consumers is lower than the number of partitions.

This can result inincreased lag, especially under high load.

FromKafka Topic Management Docs:

“Increasing the number of partitions increases consumer work, and if consumers can’t keep up, lag can accumulate.”

A is false:existing data is not redistributed.

B is false:records with the same key always map to the same partitionbased on hash.

D is not directly impacted by the partition count.