4

I'm using the community version of confluent-schema-registry. As far as I understand, too many schema under same topics may cause compatibility issues later. I tried hard to delete useless schemas in the schema registry with the methods mentioned in the link below: https://docs.confluent.io/4.0.0/schema-registry/docs/schema-deletion-guidelines.html

Afterwards the subject (topic) is empty (curl -X GET schema-registry:8081/subjects/, return []), but the schema is still there (curl -X GET schema-registry:8081/schemas/ids/25, return schema). I even tried removing the topic in the kafka-topics.sh. However, the schema seems to be still there and can be retrieved by id.

Has anyone run into the same problem? I'm curious if there is a way to remove the schema. Appreciate your help!

Sophie
  • 119
  • 2
  • 6

1 Answers1

1

Schemas are softly deleted and you need to do another step for hard delete. Check out the latest documentation

Simply deleting schemas will not free up space in the registry because this will always result in a soft delete and schema IDs are not reusable. The schema count tracks IDs, so the used number will increase as new schemas are added, regardless of whether you soft deleted schemas.

Confluent Cloud now supports “hard delete” of a schema as a two-step process (soft delete, followed by hard delete) with the use of the query string, ?permanent=true on the second delete. If your Schema Registry reaches the maximum schemas limit, you can free up space for additional schemas by following the procedure described in Hard delete a schema in Schema Deletion Guidelines.

Anton Eroshenko
  • 11
  • 3