MSBI -- SSAS -- Part-3

What is Impersonation in Data Source:

When we Design and deploy the cube OR Process the cube, The SSAS Engine needs to be interact with Source Database to refresh the cube with latest underlying data.

There are four types of impersonation modes as follows:

         





















  a) Use a specific Windows user name & password: 

                            A domain user account created specifically for this purpose. This is the best practice because all the impersonation account need is a read access to the source database.

b) Use the service account:

            The SSAS service account usually set as a powerful domain account which has access to multiple SQL Servers. Using the SSAS service account gives you access to many databases in  SQL Server. You don’t have to worry about which account have access to which databases as a) above

c) Use the credential of the current user:
                        SSAS service will use your windows account to access the database. When the cube is under development this is handy if you have access to the dev database. This way you can start the development straight away, without waiting for any account to be set-up. If you handover the BIDS project to your colleague developer however, your colleague needs to have access to that source database too. Otherwise he can’t process the cube.
Note that if you do this, when the cube is moved to production, you will need to change the account to the proper production account like a) above, or use the service account like b) above. As a developer, your Windows account does not normally have access to production databases. I’ll be surprised if it does because it creates a security issue.

d) Inherit:
           SSAS will use whatever specifies on the Database Properties. To view the Database Properties used for this, in SSMS, right click a SSAS database and choose Properties. Under Security Settings, there’s Data Source Impersonation Info. This is what Inherit uses.