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Part IX: Business Intelligence
Best Practice Warnings
SQL Ser ver 2012 implements best prac tice warnings throughout the Analysis Ser vices design environ-
ment. The warnings appear as blue underlines on the object in question, such as the dimension name
as viewed in the dimension designer. Don’t confuse these advisories with actual errors, which appear
as red underlines and which prevent a design from operating. Best practice warnings fl ag designs that
are valid but may not be optimal, depending on the application built. A list of best practice warnings
also generates in the Error List windows whenever the cube deploys.You can globally disable warnings that don’t apply to a given project by right-clicking the project within
the Solution Explorer and choosing Edit Database. Select the Warnings tab to see a list of all warning
rules. Disabling a rule keeps a warning from being checked anywhere in the project.Beyond Regular Dimensions
Dimension concepts described so far in this chapter focus on the basic functionality com-
mon to most types of dimensions. For clarity, the discussion is limited to standard, or
nondata mining, dimensions. Other discussions may cover other defi nitions of the term
dimension; the term has many meanings in the context of dimensional design.Other Dimension Types
Analysis Services recognizes more than a dozen dimension types, including Customers,
Accounts, and Products. Included templates can defi ne a table similar to the process
described for generating time dimensions. Start the Dimension Wizard, and choose
Generate a Non-Time Table in the Data Source; then select a template. You can cast existing
tables as a special type as well by assigning the Type property for the dimension (such as
Account) and the Type property for the dimension’s attributes (such as AccountNumber).Parent-Child Dimensions
Most dimensions are organized into hierarchies that have a fi xed number of levels, but cer-
tain business problems do not lend themselves to a fi xed number of levels. Relational data-
bases solve this problem with self-referential tables, which Analysis Services handles using
parent-child dimensions.A self-referential table involves two key columns — for example, an employee ID and a
manager ID like the table in Figure 53-7. To build the organizational chart, start with
the president and look for employees that she manages; then look for the employees they
manage, and so on. Often this relationship is expressed as a foreign key between the
employee ID (the primary key) and the manager ID. When such a relationship exists on the
source table, the Dimension Wizard suggests the appropriate parent-child relationship. In
the employee table example, the employee ID attribute will be confi gured with the Usagec53.indd 1208c53.indd 1208 7/31/2012 10:30:23 AM7/31/2012 10:30:23 AM
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