DBMS stands for Database Management System. It can be understood as management of the database. The process of collecting data to manage any organization is referred to as database. Here, the data may refer to input documents, reports and intermediate results which are obtained during the time of processing. These data are necessary to be ordered and maintained decently so that we can retrieve them whenever needed and for this, there is an essence of management. A Management system is referred to a set of programs that stores and retrieves the data. In short, DBMS is specified as a collection of interrelated data as well as a set of programs to store and access those data in an easy and effective manner.
Database systems are fundamentally developed for a large amount of data. While dealing with such huge amount of data, we need to take two things into account which also requires optimization and they are:
Abide by the principles of database systems, the data is stored in such a way that it acquires a lot less space as the redundant data or duplicate data has been removed before storage. Lets take an example to understand this:
In a particular bank assume that a customer is having two accounts specifying a saving account and salary account. Let’s consider that the bank stores saving account data at one place and the salary account data at another place. This leads to the duplication of information of the following person as both accounts require the customers' information like name, address, job details etc. This might create confusion or the tendency for making mistakes in the near future and to organize the data like these in a finer way, the information should be stored at a particular place such that both the accounts should be linked to this information. For example, a person's information should be recorded along with his or her account status linked with it. The exact thing is performed with the DBMS.
- Retrieval of data
While the data is stored in an optimized and systematic manner it is important to retrieve the data quickly as per needed. Database systems ensure that the data is retrieved as quickly as possible.
Applications where we use Database Management Systems are given below
We need to keep tracks of the information regarding calls made, network utilities, customer details and so on and the database systems has made it much easier to maintain such huge amount of data which tends to change every millisecond.
Industry definitely contains a manufacturing unit, warehouse or distribution center and each one of these needs a database to keep the records of entries and exits. For example, distribution center needs to keep a record of the product units that are supplied into the center along with the products that gets delivered from the distribution center daily. This is where DBMS comes into demand.
- Banking System
In order to store the records of customer information such as tracking daily credit and debit transactions, generating bank statements etc., database management system is mostly required otherwise the procedures would be very tedious and inconvenient without it.
- Education sector
Database systems are often used in schools and colleges for storing and retrieving the data such as the student details, staff details, course details, exam details, payroll data, attendance details, fees details etc. There is a huge amount of inter-related data that needs to be stored and retrieved in an efficient manner.
- Online shopping
Online shopping is the new cool trend which is going viral among the people of all generations. Popular online shopping websites such as Amazon, Flipkart etc., stores the product information, our addresses and preferences, credit details and provides us the relevant list of products based on our query. It is all possible due to the involvement of database management system.
There can be much more other applications where Database Management Systems are used. The listed above are only the major ones.
Advantages of DBMS over file system
File system had many issues at the time of its existence which caused problems in retrieving the data. It had following drawbacks:
- Data Isolation
There is a probability that the data can be stored in various files and those files may be in different formats. It will be quite difficult to write a whole new application program for retrieving the appropriate data that we desire.
- Duplication of data
There can be a duplication of the information and data in different files which may create confusion.
- Dependency on application programs
The change in files would lead to a change in application programs.
Following are some of the advantages of Database management system over file system:
- No redundant data – Redundancy is removed by data normalization.
- Data Consistency and Integrity – Data normalization takes care of data consistency and integrity.
- Secure – Each user has a different set of access which provides security.
- Privacy – Limited access.
- Easy access to data.
- Easy recovery.
Disadvantages of DBMS
- The cost for the implementation of the database management system is higher compared to the file system
Database systems are complicated to understand
Although database systems are generic which makes them suitable for various applications, however this feature affects their performance for some applications
- H.F.Korth and A. Silberschatz,"Database system concepts",McGraw Hill,2010
- A.K.Majumdar and p, Bhattacharaya,"Database Management Systems",Tata McGraw Hill,India,2004
- F.Korth, Henry. Database System Concepts. 6th edition.