As I sit here waiting for a build to complete and for a database to restore, I started fiddling with my new Windows Server 2012 instance. Weird, the available memory is super low so I take look and I see that there is a mystery SQL Server instance running something called the Windows Internal Database. What’s that all about?
I guess I have been living under a rock in terms of this subject. Windows Internal Database (WID) is a version of SQL Server 2005-2012 that Microsoft ships with Windows Server 2008/2008R2/2012/2012R2. It is a variant of SQL Express that is designed to be used by Windows Services. It cannot be uninstalled and it is used by a variety of Microsoft products, including WSUS (which is how I discovered it—I was trying to figure out why available memory dropped so dramatically after I installed WSUS), ADRMS, Resource Manager, and a couple of others.
You can connect (only locally and preferably using the same account used to install Windows) through the pipe called \\.\pipe\MICROSOFT##WID\tsql\query (for 2012). I was able to throttle memory usage on WID but expanding databases caused SQL Management Studio to hang.
Learn something new every day!