MDX - SQL Server Analysis Services 2012 Cube Development - page 202

word are only necessary if the word only consists of digits, if it is an MDX keyword,
or if it contains a space.
Tip
You could also identify each dimension member by its key, for example, the
following notation identifies a calendar year by its key: [Date].[Calendar
Year].&[2008] . Note that the ampersand ( & ) sign is followed by the key value
of 2008 . As you learned in Chapter 2 , Defining Analysis Services Dimensions ,
the attribute key doesn't have to be a numeric value. For example, the fol-
lowing notation identifies the calendar semester of a year by its key CY H1 :
[date].[Calendar Semester of Year].&[CY H1] .
A tuple identifies a single cell or multiple cells using a combination of dimensions.
Each tuple must be enclosed in parenthesis. For example, ([time]
.[year].[2011],[product].[product color].[green]) is a tuple defin-
ing the cube space consisting of all the green products and the year 2011. Note
that this tuple could contain empty cells, meaning the green products that had no
sales in 2011 as well. A tuple does not have to include a reference to each attrib-
ute from every dimension. In fact, a tuple could only refer to one attribute: ([coun-
try].[country].[England]) , which is a valid tuple.
A set consists of zero or more tuples. Each set should be enclosed in curly braces.
For example:
{
([time].[year].[2011], [product].[product
name].[sweater]),
([time].[year].[2012], [product].[product
name].[jeans])
}
The preceding example is a set consisting of two tuples. Note that the tuples you use
to construct a set must refer to the same dimensions. We cannot construct a set by
combining a tuple referencing only the Country dimension with another tuple refer-