MS SQL Server サンプルデータの AdventureWorksDW2019 スキーマを使って T-SQL を覚えるメモ。
ファクトテーブルの dbo.FactInternetSales と関連ディメンションテーブルを結合して、累計購入価格を基準にユーザーを10個のグループに分けるデシル分析をする。
declare @startdate date = '2013-01-01';
declare @enddate date = '2013-12-31';
with t1 as (
SELECT
s.[ProductKey],
s.[CustomerKey],
c.[CustomerAlternateKey],
s.[OrderDate],
s.[OrderDateKey],
c.[Gender],
c.[BirthDate],
convert(int, format(c.[BirthDate], 'yyyyMMdd')) as i_birthdate,
floor((s.[OrderDateKey] - convert(int, format(c.[BirthDate], 'yyyyMMdd'))) / 10000) as age,
c.[DateFirstPurchase],
c.[GeographyKey],
g.[CountryRegionCode],
d.[FullDateAlternateKey],
convert(varchar(7), format(d.[FullDateAlternateKey], 'yyyy-MM')) as year_month,
s.[SalesOrderNumber],
s.[SalesOrderLineNumber],
s.[OrderQuantity] * s.[UnitPrice] as revenue,
pc.[EnglishProductCategoryName] as category,
psc.[EnglishProductSubcategoryName] as subcategory,
p.[EnglishProductName] as productname
FROM
[dbo].[FactInternetSales] as s
inner join [dbo].[DimDate] as d on s.[OrderDateKey] = d.[DateKey]
inner join [dbo].[DimCustomer] as c on s.[CustomerKey] = c.[CustomerKey]
inner join [dbo].[DimGeography] as g on c.[GeographyKey] = g.[GeographyKey]
inner join [dbo].[DimProduct] as p on s.[ProductKey] = p.[ProductKey]
left join [dbo].[DimProductSubcategory] as psc on p.[ProductSubcategoryKey] = psc.[ProductSubcategoryKey]
left join [dbo].[DimProductCategory] as pc on psc.[ProductCategoryKey] = pc.[ProductCategoryKey]
where
s.[OrderDate] between @startdate and @enddate
),
t2 as (
select
t1.[CustomerAlternateKey],
sum(t1.[revenue]) as revenue
from
t1
group by
t1.[CustomerAlternateKey]
),
t3 as (
select
t2.[CustomerAlternateKey],
t2.[revenue],
ntile(10) over(order by t2.[revenue] desc) as decile
from
t2
),
t4 as (
select
t3.[decile],
sum(t3.[revenue]) as revenue,
avg(t3.[revenue]) as avg_revenue,
sum(sum(t3.[revenue])) over( order by decile) as stacked_revenue,
sum(sum(t3.[revenue])) over() as total_revenue
from
t3
group by
t3.[decile]
)
select
t4.[decile],
t4.[revenue],
t4.[avg_revenue],
100.0 * t4.[revenue] / t4.[total_revenue] as total_rate,
100.0 * t4.[stacked_revenue] / t4.[total_revenue] as stacked_rate
from
t4;
結果はこうなる。

T-SQL で顧客データをデシル分析
PowerBI で表示するとこうなる。

Power BI でデシル分析を可視化
参考図書
ビッグデータ分析・活用のためのSQLレシピ
SQL Server 2016の教科書 開発編