How to Query a Stream in ksqlDB

This is an example of a query in ksqlDB:

-- Where are Florida folks traveling to?
SELECT flight_id, to_state
FROM flights_stream
WHERE from_state = 'Florida'
EMIT CHANGES;

You can also run aggregations over a stream by using GROUP BY clauses:

-- What's Florida's favorite destination?
SELECT to_state, count(flight_id)
FROM flights_stream
WHERE from_state = 'Florida'
GROUP BY to_state
EMIT CHANGES;

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