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apache-kafkaksqldbkafka-topic

What is topic.registered in ksql when running list topics

I'm using kafka-connect to stream the rows from a mysql table to a kafka topic.

When I run this on my ksql-client:

LIST TOPICS;

I get a list of topics looking like this:

Kafka Topic                   | Registered | Partitions | Partition Replicas | Consumers | ConsumerGroups
---------------------------------------------------------------------------------------------------------
mysq-some-table               | false      | 1          | 1                  | 1         | 1
mysq-some-table2              | false      | 1          | 1                  | 1         | 1

I would like to know what is the meaning of Registered, it seems to be always false for all the topics created via kafka-connect.

I could not yet find anything in the documentation. I also noticed that as soon as I create a STREAM out of this topic, Registered becomes true.

Solution

  • Well, you're listing all of topics of Kafka.

    Some are "registered" streams/tables of KSQL, the rest are not as they are plain Kafka topics not managed by KSQL.