By default, SQL Server system objects are listed in Object Explorer in Management Studio. These system objects include system database, system tables/views/procedures and so on.
SQL Server Management Studio provides an option to hide these objects from Object Explorer to prevent *accidental* use.
To enable this option follow below steps.
Step1: Go to Tools > Options
Step2: Navigate to Environment > Startup
Step3: Check Hide system objects in Object Explorer and click OK:
Step4: An confirmation message will be displayed saying that changes will take effect after Management Studio is restarted, click on OK to continue:
Once you restart SQL Server Management Studio, you will notice that system objects are no longer listed in Object Explorer:
As you can see from above screenshot that System databases node is no longer available in Object Explorer.
What is hidden by this setting:
1. System databases – This is not hidden for SQL Server 2012
2. System Stored Procedures
3. System Tables
4. System Views
Hope This Helps!
Vishal
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Filed under: Management Studio, SQLServer, SQLServer 2005, SQLServer 2008, SQLServer 2008 R2, SQLServer 2012 
