Dimensions in the Conceptual Model - Microsoft SQL Server 2008 Analysis Services - page 43

TABLE 5.1

Attribute Properties

Name Description

Defines source of strings translating a member name to different
languages. To make the view of a member more accessible in a
multicultural organization, for each attribute member you can
define a collection of possible Translation s that specify the
language into which the member name will be translated. (The
language is defined by the Language property.) The Translation
is not usually used to reference a dimension member; more often,
it is used to display the member to the user. The member caption
is the translated name if a Translation is applied (one caption
for each language).

Translation

Defines expected size of an attribute. A count of the members of
an attribute can help determine the best internal structure for your
data. If you accurately specify a value for this property in the devel-
opment stage, the system can optimize the use of the attribute
and things will go more smoothly in later stages.

EstimatedCount

Once you've specified these properties for an attribute, you're ready to populate it.
Sometimes, populating an attribute with members is a pretty simple task. For example, the
Gender attribute generally requires only two values: male and female. On the other hand,
populating an attribute such as Customer can turn out to be a more complex task, because
the number of members in the attribute can be very large: tens and even hundreds of
millions. See Chapter 21, “Dimension and Partition Processing,” for detailed information
about loading attribute data.

Relationships Between Attributes

Even though the number of attributes in a dimension usually doesn't vary as widely as the
number of members of an attribute, it can reach to the tens and even hundreds.
Nonetheless, only one of those attributes can be the key attribute. Additional (related)
attributes define different aspects and properties of the key attribute. For example, we can
add Gender and Marital Status attributes to the Customer attribute.

Related Attributes
Every attribute has a key, but sometimes the attribute itself is the key of the dimension.
Additional attributes in a dimension can be related not only to the key attribute, but to
each other. For example, in the Customer dimension, suppose we introduce the country
and city where the customer lives. The country is a property of the city, so you get two
new attributes related to each other. We call these related attributes .

Even though dimension attributes can be related to each other or not related, all attributes
are related to the key attribute. The relationship to the key can be either direct or indirect,
through other attributes.