22. Solutions: Percentiles

Percentiles with Partitions

1.

SELECT
       account_id,
       occurred_at,
       standard_qty,
       NTILE(4) OVER (PARTITION BY account_id ORDER BY standard_qty) AS standard_quartile
  FROM orders 
 ORDER BY account_id DESC

2.

SELECT
       account_id,
       occurred_at,
       gloss_qty,
       NTILE(2) OVER (PARTITION BY account_id ORDER BY gloss_qty) AS gloss_half
  FROM orders 
 ORDER BY account_id DESC

3.

SELECT
       account_id,
       occurred_at,
       total_amt_usd,
       NTILE(100) OVER (PARTITION BY account_id ORDER BY total_amt_usd) AS total_percentile
  FROM orders 
 ORDER BY account_id DESC