Defining and Maintaining Dimensions

This topic provides an overview of dimensions and discusses how to:

Define dimensions.
Define dimension details for an Operational Warehouse - Enriched (OWE) warehouse table.
Define dimension details for a Multidimensional Warehouse (MDW) table.

Pages Used to Set Up Dimensions

Page Name	Definition Name	Navigation	Usage
Dimension	PF_DIM_DEFN	select EPM Foundation, then select Foundation Metadata, then select Metadata Creation and Editing, then select Define Dimension	Define dimension metadata.
OWE Detail for Dimension	PF_DIM_OWE_DETL	select Click the Define link on the Dimension page	Define dimension metadata details for an OWE dimension and apply security parameters.
MDW Detail for Dimension	PF_DIM_MDW_DETL	select Click the Define link on the Dimension page	Define dimension metadata details for an MDW dimension and apply security parameters.

Understanding Dimensions

Dimension metadata is associated with specific record metadata and its fields. For example, you can define the dimension DEPARTMENT that references the record DEPARTMENT_TBL and the DEPT_ID column in that record. Dimension metadata captures additional column, key, and security information that is not included with a standard datamap, such as alternate key fields and dimension security. A single dimension can be defined for both an OWE and MDW tables, enabling you to use the same dimension name for both table types.

Dimension metadata is used by the EPM Warehouses, applications, security, and KPI manager.

Dimension Security

Because EPM is delivered with no security restrictions, dimensions are also delivered unsecured. Before you can grant a user access to a dimension you must first indicate to the system that a particular dimension requires securing. Dimensions that are not secured are classified as public, or unsecured. All EPM users can view these objects.

You specify dimensions that require securing using the Dimension page. After you specify a dimension to secure you must associate that dimension with a security join table to complete dimension security. Security join tables are EPM database tables that store the security profiles for users along with the corresponding dimension values for which they have access. During security processing, a security join table acts as a lookup. For example, when a user is trying to access a row of data, the SQL that processes this request uses the security join table to identify the user and her access to the particular row of data.

A security join table must be created for every dimension that you plan to secure. Each security join table should match the key structure of the dimension table for which it is defined. Each row in a security join table identifies a user or security role and his access to a specific dimension value. A user who is granted access to multiple values in a single dimension table has several rows in the security join table. In the event that a user has access to an entire dimension, you can insert a single row designated all and prevent the table from ballooning in size with several rows of data. A user that is granted access to multiple dimensions appears in several security join tables.

Image: Account security join table

The following is an example of a security join table.

The security join table model is better than a single security output table for two main reasons: Processing smaller tables is more efficient when you are inserting or deleting data, or querying the table to determine access privileges, and modeling individual security tables enable you to be in sync with the anticipated migration to data objects in future releases.

See Defining Dimension and Metric Security.

Dimensions Page

Use the Dimension page (PF_DIM_DEFN) to define dimension metadata.

Navigation

select EPM Foundation, then select Foundation Metadata, then select Metadata Creation and Editing, then select Define Dimension

Image: Dimension page

This example illustrates the fields and controls on the Dimension page. You can find definitions for the fields and controls later on this page.

Warehouse

Indicates the warehouse layer that is associated with each dimension type.

Define

Click to access the OWE Detail for Dimension or MDW Detail for Dimension page, depending on which dimension type you are defining.

Record Name

Displays the name of the record that is associated with a particular dimension.

Owner ID

Select an owner ID for this dimension.

The owner represents an EPM functional area (such as ABM or Budgeting) that is associated with the dimension. Assign an owner ID to help organize and group the metadata—making locating and auditing easier.

OWE Detail for Dimension Page

Use the OWE Detail for Dimension page (PF_DIM_OWE_DETL) to define dimension metadata details for an OWE dimension and apply security parameters.

Navigation

select Click the Define link on the Dimension page

Image: OWE Detail for Dimension page

This example illustrates the fields and controls on the OWE Detail for Dimension page. You can find definitions for the fields and controls later on this page.

Record Information

Record Name

Select the record that you want to associate with this dimension.

Leading Key

Select a leading key for set processing.

SetID indicates that the leading key is a SetID.

Business Unit indicates that the leading key is a business unit.

None indicates that there is no leading key.

Business Key

Select a business key to serve as the primary key for the selected dimension.

Business Key Label

Select a label for your business key.

Description

Select a description for the business key field.

On Same Record indicates that the description is available in the record. If you select this option, specify a value for the Description Fieldname field.

Translate Value indicates that the description is available through the translate table.

Description Fieldname

Select the field which contains the description of the business key field.

Create Record Metadata

Select to access the Record Metadata page and define new record metadata to associate with this dimension.

If you select an existing record from the prompt, this field displays the name of the record metadata.

Security

Is Secured

Select this check box to indicate whether this dimension is secured.

If you secure this dimension, you must specify its related security join table in the Security Join Table field.

Security Join Table

Select a security join table to associate with this dimension.

The security join table is an EPM table that stores the security profiles for users along with the corresponding dimension values to which they have access. Only Dimensions that are associated with security join tables are presented to a security administrator when security is defined.

Alternate Fields

Field Name

Select an alternate name for your dimension fields.

Alternate field names share the same IDs as the primary field and can be used by different fact tables to join to the same ID.

Specifying alternate field names is optional.

MDW Detail for Dimension Page

Use the MDW Detail for Dimension page (PF_DIM_MDW_DETL) to define dimension metadata details for an MDW dimension and apply security parameters.

Navigation

select Click the Define link on the Dimension page

The MDW Detail for Dimension page contains the same fields as the OWE Detail for Dimension page with the addition of the following three fields.

Surrogate Key

Select a surrogate key for this dimension.

MDW dimensions are keyed by surrogate key, and not business unit.

Source ID

Select the source transaction system that is associated with the data in the record.

Prompt View

Enter a key to map the surrogate key to the business key.

This field enables you to select data using meaningful keys instead of surrogate keys, which are generated numbers.