Note 1: There are four types of variables that you can use:
Session
Repository
Presentation
Request
Note 2: Session Variables
A session variable is a variable that is initialized at login time for each user. When a user begins a session, the Oracle BI Server creates a new instance of a session variable and initializes it.
There are as many instances of a session variable as there are active sessions on the Oracle BI Server. Each instance of a session variable could be initialized to a different value.
There are two types of session variables:
System - A session variable that the Oracle BI Server and Oracle BI Presentation Services use for specific purposes.
System session variables have reserved names that cannot be used for other kinds of variables (such as static or dynamic repository variables and non-system session variables).
Non-system - A system variable that the administrator creates and names. For example, the administrator might create a SalesRegion non-system variable that initializes the name of a user's sales region.
The administrator creates non-system session variables using the Oracle BI Administration Tool.