From SQL Server 2008 onwards, users have to download sample databases separately. This step was taken as security measure. However, it is still notice that these sample databases still exists in many production instances. So it is recommended to not to install these sample databases to production instances as a security measure.
In this book, most of the samples if not all are referring to these sample databases. So it is advisable to download these sample databases from download.codeplex.com.
There are two sample databases dedicated to SQL Server 2012 RC0. AdventureWorks2008R2_Data.mdf and AdventureWorksDWDenali_Data.mdf are those files. So as in the previous version of SQL Server, you won’t get an installer to install sample database. Instead, you need to attach these mdf files to your SQL Server instance.
You can attach these databases only to the SQL Server 2012 RC0. There is no schema nor data changes are made to the AdventureWorks2008R2 with compared to previous sample database. Only change is the removal of the FILESTREAM property from the Product.Document table. Do not confuse with the naming of this mdf since it is still named as 2008R2.
Though there is neither schema nor data changes in AdventureWorks2008R2, there are few changes on the DW end. New fact table called FactProductInventory introduced to hold inventory fact table. Also, DimDate table was filled to match latest dates.