SELECT uniqExact(user_id) / (date_diff('day', min(min), max(max)) + if(date_diff('day', min(min), max(max)) = 0, 1, 0)) AS DailyUsers,
       uniqExact(session_id) as Sessions,
       if(isNaN(median(max - min)), 0, median(max - min)) as DurationSeconds,
       sum(count) as Events
FROM (
    SELECT min(timestamp) AS min,
           max(timestamp) AS max,
           user_id,
           session_id,
           count(*) AS count
    FROM events
    PREWHERE app_id = '{{app_id}}'
    WHERE 1 = 1
    {% if date_from and date_to %}
    AND timestamp BETWEEN '{{date_from}}' AND '{{date_to}}'
    {% endif %}
    {% if country_code %}
    AND country_code = '{{country_code}}'
    {% endif %}
    {% if event_name %}
    AND event_name = '{{event_name}}'
    {% endif %}
    {% if os_name %}
    AND os_name = '{{os_name}}'
    {% endif %}
    {% if device_model %}
    AND device_model = '{{device_model}}'
    {% endif %}
    {% if app_version %}
    AND app_version = '{{app_version}}'
    {% endif %}
    GROUP BY user_id, session_id
)