Repository and Session Variables

Session Variables: Session variables are created and assigned a value when each user logs on(when a new session is started). When a user begins a session, the Oracle BI Server creates new instances of session variables and initializes them.

There are two types of session variables:

1. System Variables: Oracle BI Server and Oracle BI Presentation Services use for specific purposes. System variables have reserved names, which cannot be used for other kinds of variables (such as static or dynamic repository variables, or for non-system session variables). 

Ex: To filter a column on the value of the variable LOGLEVEL set the filter to the Variable NQ_SESSION.LOGLEVEL.

2. Non System Variables: A common use for nonsystem session variables is setting user filters. For example, you could define a nonsystem variable called SalesRegion that would be initialized to the name of the sales region of the user.

Repository Variables :  A repository variable has a single value at any point in time.

There are two types of repository variables:

1. Static Variable: The value of a static repository variable is initialized in the Variable dialog. This value persists, and does not change until an administrator decides to change it.

2. Dynamic Variable : The values of these variables change with the values returned by queries. When the repository is started the value returned by the query in the initialization block will be assigned to the dynamic variable.