从每日数据中选择一个月内计数大于 4 的数据

Question

我正在尝试从包含每日交易的 table 中计算在过去 2 年中每个月至少进行 4 笔交易的每月商家数量（以及他们处理的总交易金额）商家。

我的查询如下：

SELECT trx.month, COUNT(trx.merchants), SUM(trx.amount)
FROM
(
  SELECT
    DATE_TRUNC('month', transactions.payment_date) AS month,
    merchants,
    COUNT(DISTINCT payment_id) AS volume,
    SUM(transactions.payment_amount) AS amount
  FROM transactions
  WHERE transactions.date >= NOW() - INTERVAL '2 years'
  GROUP BY 1, 2
) AS trx
WHERE trx.volume >= 4

我的问题是：这个查询会提取正确的数据吗？如果是这样，这是最有效的编写方式还是我可以提高此查询的性能？

Answer 1

仅获取您可以使用的商家列表，用于过滤不同数量 payement_id 和月份

的聚合值的结果

SELECT merchants
FROM transactions
WHERE transactions.date >= NOW() - INTERVAL '2 years'
GROUP BY merchants
having count(distinct DATE_TRUNC('month', transactions.payment_date))  =24
  and COUNT(DISTINCT payment_id) >= 4

对于你更新的问题只是一个建议

您可以加入 return 一年中每个月交易量超过 4 个的查询，并使用

过滤结果以直接在子查询中聚合

    SELECT trx.month, COUNT(trx.merchants), SUM(trx.amount)

    FROM (

        SELECT DATE_TRUNC('month', transactions.payment_date) AS month
            , merchants
            , COUNT(DISTINCT payment_id) AS volume
            , SUM(transactions.payment_amount) AS amount
        FROM transactions
        INNER JOIN (
         SELECT merchants
            FROM transactions
            WHERE transactions.date >= NOW() - INTERVAL '2 years'
            GROUP BY merchants
            having count(distinct DATE_TRUNC('month', transactions.payment_date))  =24
            and COUNT(DISTINCT payment_id) >= 4
        ) A on A.merchant = transactions.merchant
        WHERE transactions.date >= NOW() - INTERVAL '2 years'

        GROUP BY 1, 2
        HAVING volume >= 4
    ) AS trx

Answer 2

首先我们要考虑时间范围。您说您希望在过去 24 个月内每个月至少进行四笔交易。但是你当然不需要这个，比如说，2018 年 10 月，当运行在 2018 年 10 月 10 日查询时。你也不想只查看 2016 年 10 月的最后二十天。我们希望查看完整的 2016 年 10 月到完整的 2018 年 9 月。

接下来我们要确保商家每月至少有四笔交易。换句话说：他们每个月都有交易，而且每个月的最低交易笔数是四笔。我们可以使用 window 函数对每月交易运行进行检查。

select merchants, month, volume, amount
from
(
  select
    merchants,
    date_trunc('month', payment_date) as month, 
    count(distinct payment_id) as volume,
    sum(payment_amount) as amount,
    count(*) over (partition by merchants) number_of_months,
    min(count(distinct payment_id)) over (partition by merchants) min_volume
  from transactions
  where date between date_trunc('month', current_date) - interval '24 months'
                 and date_trunc('month', current_date) - interval '1 days'
  group by merchants, date_trunc('month', payment_date)
) monthly
where number_of_months = 24
  and min_volume >= 4
order by merchants, month;

这会为您提供符合要求的商家列表以及他们的月度数据。如果你想要商家的数量，那么聚合。例如

select count(distinct merchants), sum(amount) as total
from (...) monthly
where number_of_months = 24 and min_volume >= 4;

或

select month, count(distinct merchants), sum(amount) as total
from (...) monthly
where number_of_months = 24 and min_volume >= 4
group by month
order by month;

从每日数据中选择一个月内计数大于 4 的数据

Selecting data with counts more than 4 in a month from a daily data

sql

snowflake-cloud-data-platform