Oracle Database Discussions

Hi,

I am very new to Oracle database administration. While reading Sam Alapati's book "Expert Oracle9i Database Administration," I came across the concept of the separation of an Oracle database’s physical storage structures from its logical storage structures. In particular, Sam states the following in his book:

“This logical defining of Oracle's database structure has another fundamental motive behind it. By organizing space into logical structures and assigning these logical entities to users of the database, Oracle databases achieve the logical separation of users (owners of the database objects, such as tables) of the database from the physical manifestations of the database in terms of data files and so forth.”

I am not quite convinced about the value this separation of the physical and logical really adds to the task of database administration. Considering the way DBASE worked, i.e. each table used to be stored as a separate file, what would be lost if Oracle’s implementation were similar and each table (i.e. file) were to be assigned to a particular user. I am not sure of the value added by storing the data from more than one table in more than one file, effectively resulting in a many-to-many relationship between tables and files. Please enlighten me. I would really appreciate it.

Karim