Question

我在SQL Server 2014中有一组数据，我需要汇总到小计，并为每一行提供一个百分比。这是我需要做的简化示例：

示例数据： SELECT * FROM myTable

Week    Category    Collection  Sales
1       Red         Good        4
1       Red         Bad         5
1       Blue        Good        2
1       Blue        Bad         2
2       Red         Good        3
2       Red         Bad         1
2       Blue        Good        4
2       Blue        Bad         1

汇总部分很简单：

SELECT Week, Category, Collection, Sum(Sales) as Sales FROM myTable GROUP BY Week, Category, Collection WITH ROLLUP

Week    Category    Collection  Sales
1       Red         Good        4
1       Red         Bad         5
1       Red         NULL        9
1       Blue        Good        2
1       Blue        Bad         2
1       Blue        NULL        4
1       NULL        NULL        13
2       Red         Good        3
2       Red         Bad         1
2       Red         NULL        4
2       Blue        Good        4
2       Blue        Bad         1
2       Blue        NULL        5
2       NULL        NULL        9
NULL    NULL        NULL        22

现在，我想要了解的是汇总的每个部分的累计百分比。像这样：

Week    Category    Collection  Sales    % Total
1       Red         Good        4        .4444 (4/9)
1       Red         Bad         5        .5556 (5/9)
1       Red         NULL        9        .6923 (9/13)
1       Blue        Good        2        .5 (2/4)
1       Blue        Bad         2        .5 (2/4)
1       Blue        NULL        4        .3077 (4/13)
1       NULL        NULL        13       .5909 (13/22)
2       Red         Good        3        .75 (3/4)
2       Red         Bad         1        .25 (1/4)
2       Red         NULL        4        .4444 (4/9)
2       Blue        Good        4        .8 (4/5)
2       Blue        Bad         1        .2 (1/5)
2       Blue        NULL        5        .5556 (5/9)
2       NULL        NULL        9        .4091 (9/22)
NULL    NULL        NULL        22

*注意，我不需要显示括号中显示的分数。这只是为了更容易看到计算。

我不确定如何处理SQL以获得这种结果。如果有人能让我指出正确的方向，我将非常感激。谢谢！

Answer 1

您可以使用subquery汇总：

SELECT Week, Category, Collection, Sum(Sales) as Sales,
       1.0 * Sum(Sales) / (select sum(sales) from myTable where Week = m.Week and Category = m.Category) as [% Total]
FROM myTable m
GROUP BY Week, Category, Collection WITH ROLLUP;

但是，请注意除以零错误，您需要添加某些类型的预防，例如case表达式或类似的东西。

Answer 2

这是一种使用公用表表达式（CTE）使用分析函数预先计算可能分母然后执行聚合汇总的方法。在聚合查询中，通过使用分母中的合并运算符以及汇总中的分组集来确定百分比，使得在汇总的每个阶段，合并函数获得下一个连续分母值。您可以查看下面的查询和结果，或查看SQL Fiddle以查看设置和查询的实际效果。

with t1 as (
select week
     , category
     , collection
     , sales
     , sum(sales) over (partition by week, category) cat
     , sum(sales) over (partition by week) w
     , sum(sales) over () o
  from mytable
)
 select week
     , category
     , collection
     , sum(sales) sales
     , sum(sales)/coalesce(cat, w, o, sum(sales)) [% sales]
   from t1
  group by rollup(
        (week, o)
      , (category, w)
      , (collection , cat))
order by 1, 2, 3

<强> Results ：

|   week | category | collection | sales |  % sales |
|--------|----------|------------|-------|----------|
| (null) |   (null) |     (null) |    22 |        1 |
|      1 |   (null) |     (null) |    13 | 0.590909 |
|      1 |     Blue |     (null) |     4 | 0.307692 |
|      1 |     Blue |        Bad |     2 |      0.5 |
|      1 |     Blue |       Good |     2 |      0.5 |
|      1 |      Red |     (null) |     9 | 0.692307 |
|      1 |      Red |        Bad |     5 | 0.555555 |
|      1 |      Red |       Good |     4 | 0.444444 |
|      2 |   (null) |     (null) |     9 |  0.40909 |
|      2 |     Blue |     (null) |     5 | 0.555555 |
|      2 |     Blue |        Bad |     1 |      0.2 |
|      2 |     Blue |       Good |     4 |      0.8 |
|      2 |      Red |     (null) |     4 | 0.444444 |
|      2 |      Red |        Bad |     1 |     0.25 |
|      2 |      Red |       Good |     3 |     0.75 |

采取Yogesh的解决方案并解决其下面的缺陷与上面的解决方案相同的结果。请参阅此SQL Fiddle以查看其实际效果：

SELECT Week
     , Category
     , Collection
     , Sum(Sales) as Sales
     , Sum(Sales)
     / (select sum(sales)
          from myTable s
         where (m.category is null or Week = m.Week)
           and (m.collection is null or Category = m.Category)
       ) as [% Total]
FROM myTable m
GROUP BY Week, Category, Collection WITH ROLLUP
order by 1, 2, 3;

如何获得SQL Rollup中的总百分比？

2 个答案: