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ASSERT (NOT EXISTS)? TOPIC topicName (WITH properties)? (TIMEOUT timeout); 


Asserts that a topic exists or does not exist.

If properties are specified in an ASSERT TOPIC statement, then ksqlDB will also check that the property values match. The only properties that will be checked are PARTITIONS and REPLICAS. Trying to check any other properties will result in the assertion failing.

Properties will not be checked in an ASSERT NOT EXISTS statement.

The TIMEOUT clause specifies the amount of time to wait for the assertion to succeed before failing. If the TIMEOUT clause is not present, then ksqlDB will use the timeout specified by the server configuration, which is 1000 ms by default.

If the assertion fails, then an error will be returned.

Last update: 2023-03-31