Is there any reason why I cannot change the isolation level of a spid running against a primary database in an always on configuration?
Scenario: we are running CRM Dynamics upgrade tool. It was being blocked when trying to run the following command in SQL Server:
SET TRANSACTION ISOLATION LEVEL READ COMMITTED
On checking the error logs for the upgrade tool it says
The operation cannot be performed on database "My_CRM_DB" because it is involved in a database mirroring session or an availability group. Some operations are not allowed on a database that is participating in a database mirroring session or in an availability group.
I'd like to understand why this is. I can't find anything online in technet that says I shouldn't be allowed to set a spid's isolation level to read committed when using AlwaysOn