使用此方法，您可以检查触发器是否存在，如果不存在则创建它.不要忘记最后一个;".

Using this you can check if the trigger exists and create it if not. Don't forget the last ";".

DO $$
BEGIN
    IF NOT EXISTS (SELECT 1 FROM pg_trigger WHERE tgname = 'randomname') THEN
        CREATE TRIGGER randomname  
        AFTER INSERT OR UPDATE OR DELETE ON randomtable
        FOR EACH ROW EXECUTE PROCEDURE randomfunction();
    END IF;
END
$$;

我希望这可以为您提供帮助.

I hope this can help you.