Sometimes you roll out a database and later decide that the name you picked isn't what you really want. To rename a SQL database and it's associated files, use the Detach and Attach functions. Let's say the original database was named "MyStupidDatabase" and used files C:\MyStupidDatabase.mdf and C:\MyStupidDatabase.ldf. We want to rename the database and it's associated files to "MyFreakingAwesomeDatabase".
To detach the database, use the sp_detach_db stored procedure:
use master go sp_detach_db 'MyStupidDatabase' go
Once you've renamed your database and log files, it's time to attach the database with the sp_attach_db stored procedure:
use master go sp_attach_db 'MyFreakingAwesomeDatabase', 'C:\MyFreakingAwesomeDatabase.mdf', 'C:\MyFreakingAwesomeDatabase.ldf' go