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ID will be checked first, but if the value is the default zero UUID, topic name will be used instead.  If an ID is specified and the ID does not exist, the request will fail regardless of allow_auto_topic_creation. 
If the topic ID is not found, the request will return an UNKNOWN_TOPIC_ID error for the topic indicating the topic ID did not exist. The check for the topic ID will occur before checking authorization on the topic. Thus Thus, existence of a given topic ID is topic IDs are not considered sensitive information.

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Like the MetadataRequst, ID will be checked first, but if the value is the default zero UUID, topic name will be used instead. If an ID is specified and the ID does not exist, the request will return UNKNOWN_TOPIC_ID error for the topic indicating the topic ID did not exist. The check for the topic ID will occur before checking authorization on the topic. Thus Thus, existence of a given topic ID is topic IDs are not considered sensitive information.

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