如何对MDX子字符串成员进行分组

Question

我有一个MDX，它使用LEFT获取部门名称的子字符串，如下所示。但是，我需要按substr_dept_name成员对结果进行分组，但对如何实现此目标一无所知。任何帮助表示赞赏。谢谢；

WITH MEMBER [Measures].dummy AS 0 



MEMBER [Measures].[revenue] AS SUM(
    {revenue_value.[1]}, 
    [Measures].[amount_baseline]
  )

  MEMBER [Measures].[substr_dept_name] AS (
      LEFT(
          dept_name.CurrentMember.Name, 2
      )
  ) 
SELECT 
  {[Measures].[revenue], 
  [Measures].[substr_dept_name]} ON COLUMNS, 
  SUBSET(
    NONEMPTY(
      department.[dept_name].CHILDREN, 
      {[Measures].[revenue]}
    ), 
    0, 
    50
  ) ON ROWS 
FROM 
  (
    SELECT 
      { revenue_value.version_id.& [1] } ON 0 
    FROM 
      mytable   
  )