I had a client who wanted to change the SQL server used in a SharePoint farm. We did so using a SQL Alias and a named instance for SQL Server. The next few screenshots prove it out.
Our original server was MPNTPRJ10A.
server moving to is MPNTPRJ10B, and we want to use a named instance for SQL called N01. The SQL alias was setup on the Project Server application server as shown below.
I logged into the N01 instance on MPNTPRJ10B, and created a simple database named AAA. I simply wanted to confirm I would see the same database when connecting from the other server.
For my testing, my original SQL box also happened to be my Project Server application server. meaning, I had a single server solution. Once the SQL Alias was created I stopped the SQL Server service on mpntprj10a. I then opened SQL Management studio and connected to mpntprj10a (remember, I used an alias, so mpntprj10a actually connects to mpntprj10bN01).
If you note below, the connection does not specify an instance, because this is done through the alias. Do note, however, that the AAA database does show up, confirming I am indeed connected to the proper instance.