实际应用中，特别是一些分析报表，经常需要计算数据百分比、份额、平均值、累计占比等，在数据仓库飞速发展的今天，我们需要了解一些经常编写的MDX语句的写法，以满足工作中的需要。
由于自己写的带有很大的个性特点，不适合作为标准案例来研究，下面就通过借鉴微软示例库来介绍一下这些常用的MDX写法，以下MDX语句可以在SSAS的示例库：Adventure Works中运行。
例子模型
以下的MDX中用到的Hierarchy如下：
百分比
1）某个子项占总体的百分比。比如：每种Product的销售额占所有Product销售额的百分比。 WITH MEMBER [Measures].[Sale Amount Ratio] AS
'[Measures].[Internet Sales Amount]/([Measures].[Internet Sales Amount], [Product].[Product Categories].[All])' , FORMAT_STRING = '0.00%'
SELECT
{[Measures].[Internet Sales Amount], [Measures].[Sale Amount Ratio]} ON 0,
NON EMPTY [Product].[Product Categories].[Product Name].Members ON 1
FROM [Adventure Works]
2）某个子项占其父项的百分比。比如：每种Product的销售额占其所属的SubCategory销售额的百分比。
WITH MEMBER [Measures].[Sale Amount Ratio] AS
'[Measures].[Internet Sales Amount]/
([Measures].[Internet Sales Amount], [Product].[Product Categories].CurrentMember.Parent)'
, FORMAT_STRING = '0.00%'
SELECT
{[Measures].[Internet Sales Amount], [Measures].[Sale Amount Ratio]} ON 0,
NON EMPTY CROSSJOIN([Product].[Subcategory].[Subcategory].Members,
[Product].[Product Categories].[Product Name].Members) ON 1
FROM [Adventure Works]
3）某个子项占其祖先的百分比。比如：每种Product的销售额占其所属的Category销售额的百分比。
WITH MEMBER [Measures].[Sale Amount Ratio] AS
'[Measures].[Internet Sales Amount]/
([Measures].[Internet Sales Amount],
ANCESTOR([Product].[Product Categories].CurrentMember, [Product].[Product Categories].[Category]))'
, FORMAT_STRING = '0.00%'
SELECT
{[Measures].[Internet Sales Amount], [Measures].[Sale Amount Ratio]} ON 0,
NON EMPTY CROSSJOIN([Product].[Category].[Category].Members, [Product].[Product Categories].[Product Name].Members) ON 1
FROM [Adventure Works]
分配、分摊数量
1）根据一个Measure值来分配数量。比如：按照每种Product占总体的销售额多少来分摊成本。
WITH MEMBER [Measures].[Product Cost] AS
'([Measures].[Internet Total Product Cost], [Product].[Product Categories].[All])*
[Measures].[Internet Sales Amount]/
([Measures].[Internet Sales Amount], [Product].[Product Categories].[All])'
, FORMAT_STRING = '0.00'
SELECT
{[Measures].[Internet Sales Amount], [Measures].[Product Cost]} ON 0,
NON EMPTY [Product].[Product Categories].[Product Name].Members ON 1
FROM [Adventure Works]
2）根据一个Hierarchy来分配数量。比如：在Product Hierarchy中计算每种Category的成本的时候，可以根据每种Category下有多少个产品来进行分配。
WITH MEMBER [Measures].[Product Cost] AS
'([Measures].[Internet Total Product Cost], [Product].[Product Categories].[All])/
Count(
Descendants (
[Product].[Product Categories].CurrentMember,
[Product].[Product Categories].[Product Name],
SELF
),
INCLUDEEMPTY
)'
, FORMAT_STRING = '0.00'
SELECT
{[Measures].[Internet Sales Amount], [Measures].[Product Cost]} ON 0,
NON EMPTY [Product].[Product Categories].[Category].Members ON 1
FROM [Adventure Works]
平均值
1）简单平均值。比如：计算一个月中每天平均的销售额是多少。
WITH MEMBER Measures.[Avg Gross Profit Margin] AS
[Measures].[Internet Sales Amount]/
COUNT(Descendants([Ship Date].[Fiscal].CurrentMember, [Ship Date].[Fiscal].[Date]), INCLUDEEMPTY)
SELECT
{[Measures].[Internet Sales Amount], Measures.[Avg Gross Profit Margin]} ON COLUMNS,
[Ship Date].[Fiscal].[month].Members ON ROWS
FROM [Adventure Works]
2）加权平均值。没有想到好的例子。
基于时间的计算
1）同比和环比。比如：今年每月的销售额和去年同期相比的变化
这里要补充的是，在同比MDX中，采用COUSIN或ParallelPeriod都可以，但是采用ParallelPeriod更好一些。
2）累计到当前的统计。比如：得到一年中每一个月的累计销售额。
WITH MEMBER Measures.[Additive Internet Sales Amount] AS
SUM(
PeriodsToDate([Ship Date].[Fiscal].[Fiscal Year],[Ship Date].[Fiscal].CurrentMember),
[Measures].[Internet Sales Amount]
)
SELECT
{[Measures].[Internet Sales Amount], Measures.[Additive Internet Sales Amount]} ON COLUMNS,
[Ship Date].[Fiscal].[month].Members ON ROWS
FROM [Adventure Works]
3）移动平均值。比如：计算一种Category过去三个月的平均销售额合计。
WITH MEMBER Measures.[Average Internet Sales Amount] AS
AVG(LastPeriods(3, [Date].[Calendar].CurrentMember),
[Measures].[Internet Sales Amount])
SELECT
{[Measures].[Internet Sales Amount], Measures.[Average Internet Sales Amount]} ON COLUMNS,
NON EMPTY ([Product].[Product Categories].[Category].Members,
DESCENDANTS([Date].[Calendar].[Calendar Year].&[2002], [Date].[Calendar].[Month], SELF)
) ON ROWS
FROM [Adventure Works]