The "master" and "msdb" databases in a SQL Server installation are visible through SSMS.
However, every installation also includes a "Resource" database. This is a static database which is not directly accessed or accessible. It is installed into the SQL Server Version BINN folder and consists of both an "mdf" and "ldf" file. This is where the actual definitions of system objects are stored. This is the source database for definitions that "master" can read. And this is the actual database that is upgraded when you do a SQL Server upgrade and may also be bundled in a patch release.
So, if you filter my SQL Server Log for entries referring to this before and after the CU23 patch that I applied recently, I see :
Notice how the build version "14.00.2037" got updated to " 14.00.3381" when I applied CU23.
This Resource Database is how the "master" database update entries that I showed in my previous blog post are executed very quickly, most of them are links or hooks back to the Resource Database.
The Resource Database consists of the two files "mssqlsystemresource.mdf and mssqlsystemresource.ld" the SQL Server installed version "BINN" folder. If you copy them out and attempt to attach the copy as a database, using SSMS, you get this error :
with more details as :
This is the Microsoft Documentation on the Resource Database
When I run the queries shown in the Microsoft document, I get :
Do not attempt your own Backup/Restore of this database. But do ensure that your SQL Server Installation folder is backed up frequently, including after applying Service Packs and Cumulative Updates. You would need to refer to this backup (or such a backup from another server having the same SQL Server Version and Patch Level) if you ever need to restore this database.
No comments:
Post a Comment