SELECT id,
       message -> 'text'
FROM raw_messages
WHERE channels[1] IN (SELECT c.pubsub_channel_name
                      FROM conversation_participants AS cp
                        JOIN conversations AS c ON c.id = cp.conversation_id
                      WHERE user_id = 30)
AND   to_tsvector(message -> 'text') @@ to_tsquery('HVAC');
    

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