How Consumers Read Data
- Topic Subscription: Consumers subscribe to one or more topics from which they want to read data. This subscription determines the set of topics and partitions the consumer will process.
- Partition Assignment: Within each topic, there are multiple partitions. Kafka distributes these partitions across consumers in a consumer group to ensure that each partition is consumed by exactly one consumer at any given time. This ensures parallelism and scalability.
- Reading from Partitions: Once assigned to a partition, the consumer reads data from it. Each partition is an ordered sequence of records, and the consumer reads these records sequentially.
- Offset Management: Consumers maintain offsets to track their position in each partition. This allows them to resume reading from where they left off in case of a failure or restart.