SELECT
  DATE_TRUNC('week', u.created_at) AS cohort_week,
  DATE_TRUNC('week', e.created_at) AS activity_week,
  COUNT(DISTINCT e.user_id) AS active_users
FROM users u
JOIN events e ON e.user_id = u.id
GROUP BY 1, 2
ORDER BY 1, 2;

WITH steps AS (
  SELECT user_id,
    MAX(CASE WHEN event = 'signup' THEN 1 END) AS step_1,
    MAX(CASE WHEN event = 'onboard_complete' THEN 1 END) AS step_2,
    MAX(CASE WHEN event = 'first_action' THEN 1 END) AS step_3,
    MAX(CASE WHEN event = 'paid' THEN 1 END) AS step_4
  FROM events
  WHERE created_at > NOW() - INTERVAL '30 days'
  GROUP BY user_id
)
SELECT
  COUNT(*) AS total,
  SUM(step_1) AS signup,
  SUM(step_2) AS onboarded,
  SUM(step_3) AS activated,
  SUM(step_4) AS converted
FROM steps;

SELECT
  date,
  value,
  AVG(value) OVER (ORDER BY date ROWS BETWEEN 6 PRECEDING AND CURRENT ROW) AS rolling_7d
FROM daily_metrics;