Example (see step 4 and 5 below): Getting Top-N Sales Reps for Year and Year-1
1.Under the "Business Model and Mapping" Layer, right click the "F1 Revenue" and select "New Object" -> "Logical Column..."
2.In the "Logical Column" Window give for Name: Year Ago Revenue as seen below:
3.Goto the "Column Source" Tab and select "Derived from existing columns using an expression" radio button then click on the "Edit Expression" icon.
4.Enter the following expression in the "Expression Builder" Window by selecting "Functions" in the "Category:" list, "Time Series Functions" in the "Functions:" list then "Ago" "Time Series Functions:" section.
5.Select the "<<Measure>>" in the "Ago( )" function, then select "Logical Tables" in the
"Category:" list, "F1 Revenue" in the "Logical Tables:" list, then double click the "Revenue" in the
"Columns:" list.
Etc.

Explanation
Dimensional Modeling - Slowly Changing Dimensions
* Type 1 - Overwrite Original Value
A change does not require tracking
* Type 2 - Add a new record
With Type II SCD, a new version of the dimension record (row) is created, and the existing version is marked as history.
Each row does not correspond to a different instance of an entity but a different "state", a "snapshot" of the instance at a point in time.
Note: Tracking changes in dimension is referred in datawarehousing as slowly changing dimensions.
In the source system a lot of changes are daily made :
new customers are added,
addresses are modified,
new regional hierarchies are implemented,
or simply the product descriptions and packaging change.
These sorts of changes need to be reflected in the dimension tables and in several cases, the history of the changes also needs to be tracked.
By remembering history, we are then able to look at historical data and compare it to their current situation.

Explanation
Security Manager - is used to setup users, groups, synchronize LDAP users and Groups, set access rights for Objects (tables, columns) and to control over when and what data a user can access.

http://onlineappsdba.com/wp-content/uploads/2008/09/bi_admin_8.JPG

http://onlineappsdba.com/wp-content/uploads/2008/09/bi_admin_9.JPG
Note: When you open the administration tool, you can reach the security manager by the Menu :
Manage > Security
http://gerardnico.com/wiki/lib/exe/fetch.php?hash=29d18d
&media=http%3A%2F%2Fdownload.oracle.com%2Fdocs%2Fcd%2FE14571_01%2Fbi.1111%2Fe10543%2Fim

Content Tab
Aggregation Content
You can define the aggregation (ie the group by) of:
by hierarchy level by logical column It helps you to define an aggregate navigation

http://gerardnico.com/wiki/_media/dat/obiee/bi_server/design/fact_table/obiee_fragmentation_cont
ent_one_column.jpg?w=432
Note: logical table source
Logical table sources define the mappings from a single logical table to one or more physical
tables. A logicaltable contains one or more logical table source. The mapping between physical
columns and logical columns are done in this element.
The definition of the logical table source is used:
The Content tab of the Logical Table Source is used to define :

An action link is a link to an action that you have embedded in an analysis,
dashboard page, scorecard objective, scorecard initiative, or KPI that, when clicked, runs an
associated action.