? The Logical component consists of the overall database structure definitions, users, groups, access permissions, collations etc.
? The Physical component is the one that contains the physically represented form of the database i.e the actual files.
There are three types of files:
1. Primary data files: These contain the links to the other files. This file is the representation of the higher level of the database. (.mdf)
2. Secondary data files:
These contain the files that contain the values and actual data as in database.
3. Log files: These represent the different types of the logging output of the SQL Server, including the transaction logs.