Variables
Variables are parameters of a query that you defined in the Query Designer and that are filled with values when you execute the query or Web application. They serve as place holders for characteristic values, hierarchies, hierarchy nodes, texts and formula elements, and can be processed in different ways.
The processing type determines how a variable is filled with a value for the runtime of the query or Web application.
There are different types of variables depending on the object for which you want to define variables. These types specify where you can use the variables.

Variables are reusable objects. This means that when you define a variable for a query in the Query Designer, this variable can be used in all other queries. Variables are not dependent on the InfoProvider, only on the InfoObject. A variable that you define for an InfoObject is available in all InfoProviders that use this InfoObject.
Variables enable you to customize queries flexibly (parameterize the query). If you use variables in the Query Designer, do not select any fixed characteristic values, hierarchies, hierarchy nodes, texts, or formula elements. Instead, set up variables as place holders. These are then filled with values during query runtime (when you insert the query into a workbook, when you refresh the workbook or when you execute the query on the Web. You can use one query definition as the foundation for many different queries if you use variables.

You want to create one query for all the people responsible for customer groups, who each only evaluate the data for one customer group. In the Query Designer, you insert a variable for the characteristic Customer Group. Before the query is executed, decide for which customer group(s) you want the query to be executed.
The variables editor is available in the Query Designer for designing and changing variables. You make the settings on tab pages. These are context-sensitive and are adjusted according to the combination of variable and processing types used. This means that the variables editor only offers the selection options that are permitted for that combination of variable and processing types. For more information, see Defining Variables.
In the Variable Properties dialog box in the Properties screen area, you can change the various settings of an existing variable. For more information, see Variable Properties.
Within BI Integrated Planning , variables are used to parameterize a query, a planning function, a filter, a characteristic relationship or a data slice. For BI Integrated Planning, as well as the variable editor in the Query Designer, you have a variable wizard and a variable editor available in the planning modeler and in the planning wizard. For more information, see Variables.