Database Management System
A DBMS stores data in such as way that it becomes easy to define, construct and manipulate databases and producing information. A DBMS is a collection of programs that enable users to create and maintain a database.
Introduction of DBMS
Database is a collection of related data and data is a collection of facts & figures that can be processed to produce information. Most data represent recordable facts. For example: If we have data about marks obtained by all students, we can get information about all the toppers and average marks.
Main Points of DBMS:
A database means specifying the database types, structures, and constraints for the data to be stored in the database.
The database is the process of storing the data on some storage medium that is controlled by the DBMS.
The Database includes querying the database to gets specific data, updating the database to reflect changes, and generating reports from the data.
Users/Actors of the DBMS
A DBMS has users with different rights and permissions to use it for different purposes. Some users retrieve data and some back it up. The users of DBMS can be categories as follows:
Admins maintain the DBMS and are responsible for administrative the database. They are responsible to look after its usage and by whom it should be used.
Designers are those people who actually work on the deigning part of the database. They look after what data should be kept and what format.
End users are those who actually get the benefits of having a DBMS. The Database majorly exists for its use.
System Analyst and Application Programs (Software Engineer)
System Analysts determine the requirements of end-users and develop specifications that fulfill this requirement.
Application programmers implement this specification as programs then they test, document, and maintain these records.
Needs of DBMS
Historical information employed with their own setup file. This implied the data such as addresses may be duplicated in many separate systems such as an employee address may be held once in the payroll system and again in the personal system. This causes waste of space and inconsistency. There may be a possibility for the address to be updated in one system but not in the other system.
In the database approach, an organization attempt to built an integrated corporate database to support all the requirements of the organization. DBMS are very good at organization and maintaining large collections of persistent data.
A DBMS is like a suitcase where all the stuff(data) is put so that it is in one place and easy to reach. This protects data from unauthorized access and accidental corruption or loss due to hardware and software failure. DBMS allows concurrent access, meaning that a single data set can be accessed by more than one user at a time.