如何在MDX查询中获取特定三天内售出的前三项商品?

使用 TopCount 功能如下:

select
{
    [Measures].[Quantity],
    [Measures].[Net Sales]
}
on columns,
NON EMPTY
TopCount([Products].[Item Description].children * [Calendar].[Date].[Date], 
        3,
        [Measures].[Quantity])      
on rows
from
(
select 
{
    [Calendar].[Date].&[2015-03-23T00:00:00],
    [Calendar].[Date].&[2015-03-22T00:00:00],
    [Calendar].[Date].&[2015-03-21T00:00:00]
}
ON columns

FROM [SalesReport])

要获取每个日期的前3条记录,您可以使用 GENERATE 功能:

select
{
    [Measures].[Quantity],
    [Measures].[Net Sales]
}
on columns,
NON EMPTY
GENERATE([Calendar].[Date].[Date],  
        TopCount([Products].[Item Description].children, 
                3,
                [Measures].[Quantity])  
        )   
on rows
from
(
select 
{
    [Calendar].[Date].&[2015-03-23T00:00:00],
    [Calendar].[Date].&[2015-03-22T00:00:00],
    [Calendar].[Date].&[2015-03-21T00:00:00]
}
ON columns

FROM [SalesReport])