Professional Microsoft® SQL Server® Analysis Services 2008 with MDX

5.5. Optimizing Attributes

During the design of a dimension you might want to include certain attributes in the dimension, but not want to make the attribute hierarchies available to end users for querying. Two attribute properties allow you to manipulate visibility of attributes to end users. One property, AttributeHierarchyEnabled, allows you to disable the attribute. By setting this property to False you are disabling the attribute in the dimension; you cannot include this attribute in any level of a multilevel hierarchy. This attribute can only be defined as a member property (related attribute) to another attribute. Members of this attribute cannot be retrieved by an MDX query, but you can retrieve the value as a member property of another attribute. If you disable an attribute you might see improvements in processing performance depending on the number of members in the attribute. You need to be sure that there will be no future need to slice and dice on this attribute.

Another property called AttributeHierarchyVisible is useful for setting an attribute hierarchy to invisible for browsing; but even with this set, the attribute can be used as a level within a hierarchy and it can be used for querying. If you set this property to False, you will not see this attribute in the Dimension Browser. The properties AttributeHierarchyEnabled and AttributeHierarchyVisible are part of the Advanced group in the Properties window, as shown in Figure 5-37.

Figure 5.37. Figure 5-37