Paradigm shift - File system to DBMS

Paradigm Shift from File System to DBMS

File System manages data using files in hard disk. Users are allowed to create, delete, and update the files according to their requirement.

 The issues with file system are:

·         Redundancy of data: Data is said to be redundant if same data is copied at many places. If a student wants to change Phone number, he has to get it updated at various sections. Similarly, old records must be deleted from all sections representing that student.

·         Inconsistency of Data: Data is said to be inconsistent if multiple copies of same data does not match with each other. Inconsistency may be because of typing errors or not updating all copies of same data. If Phone number is different in Accounts Section and Academics Section, it will be inconsistent.

·         Difficult Data Access: A user should know the exact location of file to access data, so the process is very cumbersome and tedious. If user wants to search student hostel allotment number of a student from 10000 unsorted students’ records, how difficult it can be.

·         Unauthorized Access: File System may lead to unauthorized access to data. If a student gets access to file having his marks, he can change it in unauthorized way.

·         No Concurrent Access: The access of same data by multiple users at same time is known as concurrency. File system does not allow concurrency as data can be accessed by only one user at a time.

·         No Backup and Recovery: File system does not incorporate any backup and recovery of data if a file is lost or corrupted.

These are the main reasons which made a shift from file system to DBMS.

Advantages of DBMS

 DBMS helps in efficient organization of data in database which has following advantages over typical file system:

·         Minimized redundancy and data consistency: Data is normalized in DBMS to minimize the redundancy which helps in keeping data consistent. For Example, student information can be kept at one place in DBMS and accessed by different users.This minimized redundancy is due to primary key and foreign keys.

·         Simplified Data Access: A user need only name of the relation not exact location to access data, so the process is very simple.

·         Multiple data views: Different views of same data can be created to cater the needs of different users. For Example, faculty salary information can be hidden from student view of data but shown in admin view.

·         Data Security: Only authorized users are allowed to access the data in DBMS. Also, data can be encrypted by DBMS which makes it secure.

·         Concurrent access to data: Data can be accessed concurrently by different users at same time in DBMS.

·         Backup and Recovery mechanism: DBMS backup and recovery mechanism helps to avoid data loss and data inconsistency in case of catastrophic failures.