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SQL Server: resource (system database)

The resource database (physically) stores system objects (such as system base tables and system stored procedures) that come with SQL Server.
Noteably, the resource database is not intended to nor does it store user data or metadata.
In the system base table master.sys.sysdbreg, the resource database is listed with the name = 'mssqlsystemresource' and/or id=32767.
The resource database is read only.
The database file (mssqlsystemresource.mdf) and its log file (mssqlsystemresource.mdl) are located in the %programfiles%\Microsoft SQL Server\MSSQLnn.INSTANCENAME\MSSQL\Binn directory.

Timestamp of last update / version

Last update: serverproperty('ResourceLastUpdateDateTime')
Version : serverproperty('ResourceVersion')

Showing content of resource database

Mladen Prajdić https://weblogs.sqlteam.com/mladenp/2007/03/12/60132/[blogged how it is possible to make the content of resource database visible:
The instance needs to be stopped.
The database file and its log file need to be copied: 
C:\Program Files\Microsoft SQL Server\MSSQL14.MSSQLSERVER\MSSQL>copy Binn\mssqlsystemresource.?df DATA
Binn\mssqlsystemresource.ldf
Binn\mssqlsystemresource.mdf
        2 file(s) copied.
The instance is started again and the «new» database created: 
use master
go

create database [resource_copy] on
  ( filename = N'C:\Program Files\Microsoft SQL Server\MSSQL14.MSSQLSERVER\MSSQL\DATA\mssqlsystemresource.mdf' ),
  ( filename = N'C:\Program Files\Microsoft SQL Server\MSSQL14.MSSQLSERVER\MSSQL\DATa\mssqlsystemresource.ldf' )
for attach
go

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