Guy and Clarisses relationship is hard to understand. However, I would say they were good friends. Clarisse is curious about Guys field of work. She asked him many questions, walked him and talked to him everyday he had work, and made little leaf things for him.
SQL Server Master Database File (MDF/.mdf) Overview. An MDF (Master Database File) file is the primary database file of Microsoft SQL Server with an extension .mdf, which contains the data as well as schema. We can create more than one data file with .mdf file extension for a database whether it does exist in a filegroup or by generating a new filegroup. Database Files.
The ndf file extension is used for Microsoft SQL Server secondary data files. The secondary data file is created by Microsoft SQL Server, when the primary data file (mdf file) is full of data and other data cannot be stored in it.