RFM 分析——价值不断变化

Question

进行以下查询。

SELECT
    customer_id,
    NTILE(5) OVER (ORDER BY MAX(oms_order_date)) AS r_score
FROM 
    mdwh.us_raw.l_dmw_order_report
WHERE 
    quantity_ordered > 0
    AND customer_id IS NOT NULL
    AND customer_id != ('')
    AND UPPER(line_status) NOT IN ('','RETURN', 'CANCELLED')
    AND UPPER(item_description_1) NOT IN ('','FREIGHT', 'RETURN LABEL FEE', 'VISIBLE STITCH')
    AND (quantity_ordered * unit_price_amount) > 0
    AND extended_amount < 1000 --NO BULK ORDERS
    AND oms_order_date BETWEEN '2020-01-01' AND '2020-01-01'
    AND SUBSTRING(upc,1,6) IN (SELECT item_code FROM item_master_zs WHERE new_division BETWEEN '11' AND '39')
GROUP BY
    customer_id
ORDER BY
    customer_id

我在这里所做的就是，在给定一些条件的情况下，为我提供唯一的客户 ID，然后将他们的最新购买日期聚类为五分位数，并在第二列中为我提供分数。但是每次我运行查询时， r_score 值一直在变化？我究竟做错了什么..？这是 table 的片段（同样，r_score 值不断变化）：

Answer 1

ntile() 的问题在于，它通过在不同的组中放置相同的值来确保组完全相同的大小。

因此，我通常手动计算，使用 rank():

ceil(rank() over (order by max(oms_order_date)) * 5.0 /
     count(*) over ()
    ) as r_score

如果您使用 row_number()，您将得到 ntile() 的等价物。

如果您想使用 ntile()，您可以使用额外的 order by 键，这样排序键是唯一的。

===================

2/17/20 5:18PM 编辑

这是我使用的新代码：

SELECT
    customer_id,
    CEIL(RANK() OVER (ORDER BY MAX(oms_order_date)) * 5 / COUNT(*) OVER ()) AS r_score,
    CEIL(RANK() OVER (ORDER BY COUNT(client_web_order_number)) * 5 / COUNT(*) OVER ()) AS f_score,
    CEIL(RANK() OVER (ORDER BY AVG(extended_amount)) * 5 / COUNT(*) OVER ()) AS m_score,
    (r_score || f_score || m_score) AS rfm_score
FROM 
    mdwh.us_raw.l_dmw_order_report t1
WHERE 
    quantity_ordered > 0
    AND customer_id IS NOT NULL
    AND customer_id != ('')
    AND oms_order_date IS NOT NULL
    AND UPPER(line_status) NOT IN ('','RETURN', 'CANCELLED')
    AND UPPER(item_description_1) NOT IN ('','FREIGHT', 'RETURN LABEL FEE', 'VISIBLE STITCH')
    AND (quantity_ordered * unit_price_amount) > 0
    AND extended_amount < 1000 --NO BULK ORDERS
    AND oms_order_date BETWEEN '2020-01-01' AND '2020-01-10'
    AND SUBSTRING(upc,1,6) IN (SELECT item_code FROM item_master_zs WHERE new_division BETWEEN '11' AND '39')
GROUP BY
    customer_id
ORDER BY
    customer_id

现在的问题是我得到了一些空白的行 r_score，并且最大值是 4 而不是 5..

RFM 分析——价值不断变化

RFM Analysis - Value keeps changing

sql

amazon-redshift

aginity

2/17/20 5:18PM 编辑