如何汇总交易数据以进行报告？ （SQL Server）

Question

我有一些看起来像这样的数据：

+----+-----------+--------+---------+--------+
| id | timestamp | amount | product | method |
+----+-----------+--------+---------+--------+
|  1 | 6/5/2018  |      4 | apple   | cash   |
|  2 | 6/5/2018  |      7 | apple   | cash   |
|  3 | 6/6/2018  |      3 | orange  | card   |
|  4 | 6/6/2018  |      9 | orange  | cash   |
|  5 | 6/7/2018  |      4 | orange  | card   |
|  6 | 6/7/2018  |      8 | apple   | card   |
+----+-----------+--------+---------+--------+

每天有数十万笔交易。

我想根据这些数据生成图表，这些图表可以是每天，每周，每月或数月。我当时想我应该编写一些c＃代码来循环遍历每天，产品，方法的组合，然后运行查询以获取总计并产生如下数据：

+------+-------+-----+------------+-----------+-------+
| year | month | day | dimProduct | dimMethod | total |
+------+-------+-----+------------+-----------+-------+
| 2018 |     6 |   5 | apple      | cash      |    11 |
| 2018 |     6 |   5 | apple      | card      |     0 |
| 2018 |     6 |   6 | apple      | cash      |     0 |
| 2018 |     6 |   6 | apple      | card      |     0 |
| 2018 |     6 |   7 | apple      | cash      |     0 |
| 2018 |     6 |   7 | apple      | card      |     8 |
| 2018 |     6 |   5 | orange     | cash      |     0 |
| 2018 |     6 |   5 | orange     | card      |     0 |
| 2018 |     6 |   6 | orange     | cash      |     9 |
| 2018 |     6 |   6 | orange     | card      |     3 |
| 2018 |     6 |   7 | orange     | cash      |     0 |
| 2018 |     6 |   7 | orange     | card      |     4 |
+------+-------+-----+------------+-----------+-------+

但是后来我觉得...有一种比编写代码的方法更好的方法，该代码可以运行数百万个查询，并且需要花费数天的时间才能运行，然后随着新数据的传入而难以更新。

有什么建议吗？

Answer 1

由于您需要生成不存在的数据，因此您需要包括数据库引擎，因为答案将取决于供应商。

---

对于您已有的数据，您需要从日期列中提取日期部分，将它们分组并包括sum(amount)作为总数：

select
  year(timestamp) as year,
  month(timestamp) as month,
  day(timestamp) as day,
  product as "dimProduct",
  method as "dimMethod",
  sum(amount) as total
from yourtable
group by year(timestamp), month(timestamp), day(timestamp), product, method

Answer 2

您可以添加DimDate而不是分解日期元素。比用汇总数据创建事实表。