为多个分层组优化 SUM OVER PARTITION BY

Question

我有一个 table 如下所示：

Region    Country    Manufacturer    Brand    Period    Spend
R1        C1         M1              B1       2016      5
R1        C1         M1              B1       2017      10
R1        C1         M1              B1       2017      20
R1        C1         M1              B2       2016      15
R1        C1         M1              B3       2017      20
R1        C2         M1              B1       2017      5
R1        C2         M2              B4       2017      25
R1        C2         M2              B5       2017      30
R2        C3         M1              B1       2017      35
R2        C3         M2              B4       2017      40
R2        C3         M2              B5       2017      45

我需要在不同的组中找到 SUM([Spend]，如下所示：

整个table中所有行的总支出
每个地区的总支出
每个地区和国家组的总支出
每个地区、国家和广告商组的总支出

所以我在下面写了这个查询：

SELECT 
    [Period]
    ,[Region]
    ,[Country]
    ,[Manufacturer]
    ,[Brand]
    ,SUM([Spend]) OVER (PARTITION BY [Period]) AS [SumOfSpendWorld]
    ,SUM([Spend]) OVER (PARTITION BY [Period], [Region]) AS [SumOfSpendRegion]
    ,SUM([Spend]) OVER (PARTITION BY [Period], [Region], [Country]) AS [SumOfSpendCountry]
    ,SUM([Spend]) OVER (PARTITION BY [Period], [Region], [Country], [Manufacturer]) AS [SumOfSpendManufacturer]
FROM myTable

但是对于仅 45 万行的 table，该查询需要 >15 分钟。我想知道是否有任何方法可以优化此性能。提前感谢您的 answers/suggestions！

Answer 1

在这里使用交叉应用来加快查询速度：

 SELECT 
     periodyear
    ,[Region]
    ,[Country]
    ,[Manufacturer]
    ,[Brand]
    ,SUM([Spend]) OVER (PARTITION BY  periodyear AS [SumOfSpendWorld]
    ,SUM([Spend]) OVER (PARTITION BY  periodyear, [Region]) AS [SumOfSpendRegion]
    ,SUM([Spend]) OVER (PARTITION BY  periodyear, [Region], [Country]) AS [SumOfSpendCountry]
    ,SUM([Spend]) OVER (PARTITION BY  periodyear, [Region], [Country], [Manufacturer]) AS [SumOfSpendManufacturer]
FROM myTable
  cross apply (select YEAR([Period]) periodyear) a

Answer 2

你对问题的描述向我grouping sets暗示：

SELECT YEAR([Period]) AS [Period], [Region], [Country], [Manufacturer], 
       SUM([Spend])
GROUP BY GROUPING SETS ( (YEAR([Period]),
                         (YEAR([Period]), [Region]),
                         (YEAR([Period]), [Region], [Country]), 
                         (YEAR([Period]), [Region], [Country], [Manufacturer])
                        );

我不知道这是否会更快，但它肯定看起来更符合您的问题。

Answer 3

SUM() OVER()老派：

SELECT 
      [Period]
    , [Region]
    , [Country]
    , [Manufacturer]
    , [Brand]
    , (SELECT SUM([Spend]) FROM myTable t WHERE e.[Period] = t.[Period] GROUP BY [Period]) AS [SumOfSpendWorld]
    , (SELECT SUM([Spend]) FROM myTable t WHERE e.[Period] = t.[Period] AND e.Region = t.Region GROUP BY [Period], [Region] ) AS [SumOfSpendRegion]
    , (SELECT SUM([Spend]) FROM myTable t WHERE e.[Period] = t.[Period] AND e.Region = t.Region AND e.Country = t.Country GROUP BY [Period], [Region], [Country] ) AS [SumOfSpendCountry]
    , (SELECT SUM([Spend]) FROM myTable t WHERE e.[Period] = t.[Period] AND e.Region = t.Region AND e.Country = t.Country AND e.Manufacturer = t.Manufacturer GROUP BY [Period], [Region], [Country], [Manufacturer] ) AS [SumOfSpendManufacturer]
FROM myTable e

虽然这不是一个优雅的方法，但它完成了工作。我强烈建议查看 table 并对其进行分析，以了解哪种替代方法最适合您的情况。如果您觉得这是一个死胡同，那么我建议使用 temp tables 来加快速度。例如，您可以 select 基于句点的行并使用批量复制将它们直接插入到临时 table，然后施展您的魔法。我看到 tables 迫使我使用临时 tables 而不是简单的 select 查询。其他人强迫我将 table 扩展为两个 table。

所以，它并不总是那么干净整洁！

我希望这会给您带来另一种见解，对您的旅程有所帮助。

为多个分层组优化 SUM OVER PARTITION BY

Optimizing SUM OVER PARTITION BY for several hierarchical groups

sql

sql-server

window-functions

partition-by