It is efficient since it does not have the same computing overhead as using a database.
It is flexible because developers can design and implement file structures and file processing methods specific for the problems.
Cons of Using File Systems
It requires the developers to define and implement file structures and file processing methods for each application.
It is unable to span files over several disks.
It is difficult and expensive to change the format of files and the specific files that are used by the programs.
File processing leads to a lack of consistency between files.
The classic example is when an employee leaves a company, his name is taken off the payroll system, but his security access is not revoked.
File processing also results in wasted storage.
Summary
In conclusion, files are a useful alternative to databases only where
the information is only going to be accessed by a single user,
speed of data input or searching is vital, or
the amount of data being stored is relatively small.
Using databases can relieve developers’ task of designing file structures for their applications.
However, flexibility is the cost.
In fact,
a DBMS is, first and foremost, a disk access manager.
For most cases, developers choose to use databases.