Technical data

Chapter 3 Understanding Analytic Models

SALARY

2004/01 2004/02 2004/03

Carlos

Chang

John

Linda

2004/01 2004/02 2004/03

Carlos

Chang

John

Linda

(Existing MONTHS

dimension)

(New EMPLOYEES

dimension)

SALARY

data cube with attached MONTHS dimension and new EMPLOYEES dimension

Formulas and User Functions

You c re

ate formulas to define the relationships among the data cubes in an analytic model. For example, this

formul

a for the G ROSS_MARGIN data cube defines the relationship between GROSS_MARGIN and other

data cu

bes called SALES and COST_OF_GOODS:

SALES -

COST_OF_GOODS

The analytic calculation engine recalculates the values in the GROSS_MARGIN data cube whenever the end

user changes the values in the SALES or COST_OF_GOODS data cubes and saves those changes.

Formulas refer to kinds of information as defined by data cubes. Formulas do not refer to specific values. The

relationship between GROSS_MARGIN, SALES and COST_OF_GOODS remai ns true regardless of the

specific data contained in these data cubes. You can attach new products or months to the data cubes without

changing or copying the formula because the relationships between the data cubes have not changed.

User f

unctions serve several purposes. You can create a user function that contains all or part of a formula, and

apply

this user function to calculate multiple data cubes. You can also create user functions to define filter

funct

ions and rules for aggregating dimension members.

See C

hapter 10, “Creating Rules, Formulas, and User Functions,” page 111 and Chapter 9, “Creating

Hierarchies,” Understanding Dimen sion Members, page 73 .