Working with local SQLServer can sometimes be challenging, if you don’t have any tools, to access a database. For administrational reasons it could be helpful, to gain access to SQL Server you can simply use the commandline cmd.exe or powershell tools. This is nothing new, but I think, it is not so common.
So, to start open up cmd.exe and type for example
sqlcmd -S (localdb)\v11.0 -E
This command opens (-S) a trusted (-E) connection to you local instance of a SQLLocalDB 2012. Note: this command ist case sensitive.
Than cmd prompt for further commands “1>”. Here you can type T-SQL statements like
exec sp_databases GO
This prompts for a Terminator for example (GO + <Enter-Key>).
After this your SQL Server instance runs this command and results with a number of databases, that are attached.
If you like to know more about read here: https://msdn.microsoft.com/en-us/library/ms162773.aspx