As many of you aware, SQL Server can be a bit of a pig when it comes to system resources on your development machine. As part of the 2012 products Microsoft has added SQL Server 2012 Express LocalDB which is a happy medium for myself when thinking about having to install a full blown SQL Server on my box. This however does not work in all cases for all development but if you are doing web or local client development then it should suffice. On the other hand, if you are working with technologies like SharePoint or trying to run Team Foundation Server on your local box then you will be out of luck while using LocalDB.
To start of with, the localDB setup is delivered and packaged with Visual Studio 2012 RC. If you want to get the stand-alone installer you can download it here in either the 32 or 64 bit flavors. Once you get it installed you can start using it right away in either Visual Studio 2010 or the new Visual Studio 2012 RC.
To get started you can open the SQL Server object explorer in Visual Studio by clicking the menu option View –> SQL Server Object Explorer. This will bring up to the navigation pane where you can add a SQL Server. Once you add the SQL Server you will be prompted with the “Connect to Server” dialog to enter the server for which you can use “(localdb)\v11.0”. Click connect and you should be connected to your localDB where you can create and manage databases from Visual Studio 2010, Visual Studio 2012 or SSMS.
Once you have started creating databases here you can use the database projects in Visual Studio with these database as well as use the (localdb)\v11.0 server name inside your connections string information for your development environment.
Hope this helps someone get started with SQL Server 2012 Express LocalDB! It provides a great balance for developing against SQL Server 2012.