元组函数从集合中检索元组,或通过解析元组的字符串表示来获取元组。
元组函数,与成员函数和集合函数一样,对于协商分析服务中的多维结构至关重要。
MDX 中有三个元组函数:Current(MDX)、Item(元组)(MDX)和 StrToTuple(MDX)。 以下示例查询展示了如何使用它们:
WITH
//Creates a set of tuples consisting of Years and Countries
SET MyTuples AS [Date].[Calendar Year].[Calendar Year].MEMBERS * [Customer].[Country].[Country].MEMBERS
//Returns a string representation of that set using the Current and Generate functions
MEMBER MEASURES.CURRENTDEMO AS GENERATE(MyTuples, TUPLETOSTR(MyTuples.CURRENT), ", ")
//Retrieves the fourth tuple from that set and displays it as a string
MEMBER MEASURES.ITEMDEMO AS TUPLETOSTR(MyTuples.ITEM(3))
//Creates a tuple consisting of the measure Internet Sales Amount and the country Australia from a string
MEMBER MEASURES.STRTOTUPLEDEMO AS STRTOTUPLE("([Measures].[Internet Sales Amount]" + ", [Customer].[Country].&[Australia])")
SELECT{MEASURES.CURRENTDEMO,MEASURES.ITEMDEMO,MEASURES.STRTOTUPLEDEMO} ON COLUMNS
FROM [Adventure Works]