Perspectives are a way to reduce the complexity of cubes by hidden elements like measure groups, measures, dimensions, hierarchies etc.Perspectives do not require any storage beyond their definition.
Perspectives vs. ViewsPerspectives are similar to views in a relational database in that they narrow down what can be seen from a single cubePerspectives are different from views in that : They cannot combine multiple cubes to look like oneThey are not securable objects
Working with PerspectivesIn BIDS, if we open an SSAS project there is a Perspectives tab.This tab shows the cube obejcts, object type, measure groups, Dimensions and their heirarchies and attributes, KPIs actions and calculcations etcAll these items are available for you to turn off and on in a Perspective.In the Perspective column give a name to the Perspective and tick or untick the items as you want based on the specifications you decide for the end user to see.You can create more than one perspective for a SSAS project.
When this is published, the client tools will show both the cube as well as the perspectives.
If excel is used to access the cube, then in excel it shows both the cube and the perspective.
The idea behind this is to simplify their view so that it is simple for them to use.
Perspectives are often most useful when used in pre-formatted reports such as Excel or Performance Point Services analytic Chart and Analytic grids
Can i create perspectives for different roles and restrict it as per that? I mean Role A should be able to view only Perspective A, Role B only Perspective B?
Yes you can. You can create a perspective for Role A and call it roleA and similarly for role B so that you don't get confused when you are gicing access.