Tableau, Power BI, and Looker Fundamentals Questions

WITH monthly AS (
  SELECT
    user_id,
    TO_CHAR(order_date, 'YYYY-MM') AS year_month,       -- format month
    SUM(amount) AS monthly_revenue
  FROM orders
  WHERE order_date >= (CURRENT_DATE - INTERVAL '11' MONTH)   -- last 12 months inclusive
    AND order_date <= CURRENT_DATE
  GROUP BY user_id, TO_CHAR(order_date, 'YYYY-MM')
)
SELECT
  user_id,
  year_month,
  monthly_revenue,
  SUM(monthly_revenue) OVER (
    PARTITION BY user_id
    ORDER BY year_month
    ROWS BETWEEN UNBOUNDED PRECEDING AND CURRENT ROW
  ) AS running_total
FROM monthly
ORDER BY user_id, year_month;

ALTER TABLE orders ENABLE ROW LEVEL SECURITY;
    CREATE POLICY tenant_isolation ON orders
      USING (tenant_id = current_setting('app.current_tenant')::int);

-- compare pageview/event ingestion to reporting table
SELECT day, count(*) as raw_events
FROM raw_events
WHERE event_type='page_view' AND day BETWEEN '2025-10-01' AND '2025-11-30'
GROUP BY day;
SELECT day, count(*) as reported_events
FROM analytics_facts
WHERE event='page_view' AND day BETWEEN '2025-10-01' AND '2025-11-30'
GROUP BY day;

WITH steps AS (
  SELECT user_id,
    MAX(CASE WHEN event='visit' THEN ts END) AS visit_ts,
    MAX(CASE WHEN event='signup' THEN ts END) AS signup_ts,
    MAX(CASE WHEN event='purchase' THEN ts END) AS purchase_ts
  FROM analytics_facts
  WHERE day BETWEEN ...
  GROUP BY user_id
)
SELECT
  count(*) FILTER (WHERE visit_ts IS NOT NULL) as visits,
  count(*) FILTER (WHERE signup_ts IS NOT NULL) as signups,
  count(*) FILTER (WHERE purchase_ts IS NOT NULL) as purchases
FROM steps;

SUM([Revenue]) - SUM([Cost])
/
SUM([Revenue])

SUM([Revenue] - [Cost]) / SUM([Revenue])

Profit Margin =
DIVIDE(
    SUM('Sales'[Revenue]) - SUM('Sales'[Cost]),
    SUM('Sales'[Revenue]),
    0
)

measure: profit_margin {
  type: number
  sql: (SUM(${revenue}) - SUM(${cost})) / NULLIF(SUM(${revenue}),0) ;;
  value_format_name: "percent_2"
}