What is DBMS? Users, Types, Architecture, Functions, Examples.
What is DBMS? Users, Types, Architecture, Functions, Examples. You can find many guide about DBMS where they will give you some brief introduction of few concepts of DBMS. But here we have made an ultimate guide for you about database management system. In this article, you will all the details about DBMS from history, present to future. The table of content is given below for the various topics of DBMS.
Table of Contents
What is DBMS? Users, Types, Architecture, Functions, Examples.
Traditional file system
Before there is no existence of computer, a file system was used to maintain the data and records manually. Files were used to store the data and it also makes it easier to find any sort of information from the files. But the scope of this system is quite less in small organizations but it is good for a small amount of data in small organizations.
To overcome the problems of the manual file system, a Traditional File System was introduced which was entirely a system based on computer. Under this system, all the information is stored in different files of the computer. It also stores the whole data in a manner that it becomes easy for the departments of the large industries have their different files and it forms redundancy of the data.
To exemplify, to understand the statement in a better way we will take an example of college data where the data of the students stored in three different files such as a separate data file for Library, the second one is for examinations and the last one is stored for registration. All these files create duplicate data such as roll number of students, their name and father’s name too.
Get clarity of this concept with a rudimentary diagram as given below:
Data and the independency are the main highlights in this diagram. It indicates that the data and the programs depend on each other. Due to this dependency, changes in one file can affect the other files too.
There are some of the characteristics of traditional File System which are given below:
- All the data of an organization is stored in a group of files.
- All the data files are dependent on each other.
- The files are designed with the help of programming languages such as COBOL, C and C++.
- The data stored in each file belongs to a definite area like students fees, library and student examinations.
- Flexibility is quite low and contains a number of limitations.
- Hard to maintain the file processing system.
- A single change in one file can affect the others too and increase the burden of the programmer.
- Flat files are stored files in traditional file processing systems.
Overall, this system is a good approach for the storage of data files as compare to manual filing system but still, it had many limitations that can only overcome with the help of Database Management System.
Also Read: Learn More About Traditional File System
What is Database?
The database is a collection of organized set of data that make it straightforward to access, manage, manipulate and update as well. In short, it makes the management of data easy. Moreover, the data can be in any form related to facts such as pictures, file, images, pdf and so on.
Here are a few examples of our daily life. To exemplify, the online telephone directory uses the database to the entire data related to the clients including their name, contact number, address and so on. At the same token, the database is also used in electricity services for handling bills, issues related to clients and manages fault data and many more. Moreover, you can also take an example of Facebook that needs to store the whole data related to their members, friends, activities, messages and advertisements.
Also Read: Learn More About Database
History of DBMS
The origin of the database exits before the invention of the computer as it is needed in libraries, governmental, business and medical records. Moreover, it was observed that they required maintaining and storing the data for retrieval and they find some ways at that time. With the introduction of the computer, it becomes quite easy, time effective and consumes less space to collect as well as maintain the database.
- Ancient Times: RAM was expensive and limited, lower the productivity of programmer.
- 1960’s: File-base system and data maintained in a flat file.
- 1970’s: Era of non-relational database (CODASYL DSTG model, IDMS was popular)
- 1980’s: Era of relational database and Database Management System (DBMS).
- 1990’s: The era of OODBMS, ORDBMS and XML
- Early 21st: Started with Y2K(Year 2000) problem and right now Sybase or SQL Server’s transact SQL, PostgresSQL and Oracle’s PL or SQL are used to handle all the databases. IBM, Microsoft and Oracle dominated the market share of databases
Introduction to DBMS
Database Management system i.e. DBMS is a collection of programs for managing data and simultaneously it supports different types of users to create, manage, retrieve, update and store information.
For example, from a small startup firm to the multinational companies and industries managing a huge amount of data becomes a mess. So, the software like the DBMS brought a revolution in many fields regarding efficient information management.
DBMS Versus File system
The following are the differences between DBMS and File System:
|Basis of difference||Database Management System||File System|
|User requirement||It is a set of data and the user is not required to write the processes in DBMS.||It is also a collection of data but the user needs to write the procedures for handling the Database.|
|Protection mechanism||DBMS provides a brilliant mechanism for protection.||It is hard to protect a file.|
|Techniques||It has loads of different techniques to store and retrieve data.||It does not have the efficiency to store the data and retrieve it in a good way.|
|Locking||It uses some sort of locking to control the unauthorized access to the data.||In this type of data system, there is no control over the redirection and update of the information.|
|Data redundancy||It minimizes the chances of duplication of the data.||Data redundancy is more in this type of system.|
|Data Inconsistency||Less inconsistency in data.||More data inconsistency.|
Definition of DBMS
- According to Prakash Naveen, “Database is a mechanized shared formally defined and central collection of data used in an organization.”
- M. Martin Described, “Database is a collection of inter-related data stored together without harmful or unnecessary redundancy to serve multiple application.”
- Mac-Millan dictionary of Information Technology explained database as, “a collection of inter-related data stored so that it may be accessed by authorized users with simple users-friendly dialogues.”
Functions of DBMS
The general motive behind the development of the database management system is to manage the information as a whole. Its objective is to make the data easily accessible, rapid, less costly and flexible for its users.
- It decreases the duplication of data and minimizes data redundancy. In this way, the extra space covered by duplicate data could be used for other purposes and there is no more wastage of space.
- The DBMS is easy to use and learn too. Moreover, the packages of DBMS are user-friendly and very flexible.
- There is data independence as the user can do changes at any level of the database with no bad impact on other levels such as hardware and software processes.
- This one is economically good for everyone. One can use, store and manipulate data at a very affordable price.
- It can be accessible by multiple users and helps to recover data in case it is not saved by the user. The system can easily recover the data in no time and it maintains accuracy and integrity.
- It prevents unauthorized access to the data and the data remain private. Through centralized control, DBMS makes it sure that proper security is provided to the data.
- It is useful for the retrieving, analyzing and storing the data.
Architecture of DBMS
The design of DBMS depends on its architecture. A large amount of data on Personal Computers, web servers, database servers and other elements that are linked with networks can be dealing with the help of basic client or server architecture. Many PCs and workstations are part of Client architecture which is connected over the network. The architecture of DBMS relies upon how the users are linked to the database. There are three kinds of DBMS Architecture which will be discussed below:
- Tier-1 Architecture: In this type of Architecture, the data is directly provided to the customer and the user can directly use the database through the computer. Any changes required can be done easily by the user and no handy tool is provided to end-user. It is used for enhancement of the local application where the programmer can directly communicate with the database of the application for rapid response.
- Tier-2 Architecture: It is similar to the basic client-server. In the two-tier architecture, the applications from the end of the client can communicate at the server-side with the database. This interaction uses Application Program Interface like ODBC and JDBC. The user interfaces, as well as application programs, run on the side of the client. The server side is responsible for providing the functionalities such as query processing and management of transactions.
- Tier-3 Architecture: This architecture contains one more layer between the client and the server. There is no direct communication between the client and the server. This is used in case of large application on the web.
Users in DBMS
There are different types of users and can retrieve data on demand using the applications and interfaces provided by DBMS. They are:
- End user= The users who deal with the database at the terminal end they can be casual users or native database user.
- Application programmers- The users who develop the applications in different languages (Java, .net, Cobol, php etc.) to interact with database.
- System Analyst- – System Analyst is responsible for overall technical, economical and feasibility aspects of the DBMS.
- Database administrators- everything related to DBMS like policies and strategies is handled by the DBA. DBA can be a single person or group of many persons.
- Sophisticated Users- They are the SQL programmers, who deal directly with the database. They write queries to delete/select/insert and update the database.
Also Read: Learn More About Database Users
Examples of DBMS
DBMS is widely used by approximately all the companies and there are loads of examples present there. According to their requirements, large as well as small companies use DBMS to manage their data. Here are some of the examples of DBMS:
- MySQL Database: It was founded in the year 1995. MySQL was acquired by Sun Microsystems in 2008 and the sun Microsystems was acquired by Oracle after two years. MySQL is one of the largest open-source companies in the world and is popular due to its high level of efficiency, reliability and cost.
- MS-Access: It was developed by Microsoft and this computer-based application is used to form as well as create the databases on the desktop of the computers. It can be used for personal work and for small scale business that required a database. It is easy as it uses the graphical user interface.
- Oracle database: It is the fourth relational database management system which is developed by Oracle Corporation. Oracle database is useful for storing a large amount of data, especially by large organizations. Moreover, it is very flexible and very beneficial for shared SQL and locking.
- DB2: It was founded by IBM Corporation and is lucrative to store data for big industries. It is also a relational database management system and the extended version of DB2 supports object-oriented features. However, this one is very expensive that is a big problem.
- Microsoft SQL Server: As the name indicates, it is an RDBMS from Microsoft company which creates computer databases for MS- Windows. Based on customer’s requirements, Microsoft has developed various versions of SQL Server.
Also Read: Learn More 25 Examples of DBMS
Data Models in DBMS
|Concepts||Relational Model||Network Model||Hierarchic Model|
|Meaning||Data is stored in rows and columns in the table.||Data is arranged in graphical manner with child and parent graph.||Data is arranged in a tree- like structure.|
|Item||Role name or Domain||Data item type||Item or Field|
|Item Value||Component||Data item occurrence||Value|
|Type of entity||Relation||Record type||Entry or Segment type|
|Entity Instance||Tuple||Record occurrence||Entry or Segment occurrence|
|Relationship||Foreign key comparable underlying domains||Set type||Hierarchic|
|Relationship instance||Set Occurrence||Assembly|
|Data Administrator view||Data model||Logical structure||Logical structure|
|Definition of data administrator view||Data Model definition||Schema||Schema|
|User View||Data sub model|
|Definition of user view||Data sub model definition||Sub Schema||Sub Schema|
|Entry points||Primary Key||Singular sets CALC records||Root Group|
|Single unique or Identifier||Candidate Key||Key||Root segment sequence (unique)|
Also Read: Learn More Data Models In DBMS
Types of DBMS
There are many types of DBMS available in the market today and they are as below:
Based on the data model
- Relational database
- Object oriented database
- Object relational database
- Network database
Based on the number of users
- Single user
- Multiple users
Based on the sites over which network is distributed
- Centralized database system
- Parallel network database system
- Distributed database system
- Client-server database system
- Multi-tier client-server database system
Based on the cost
- Low cost DBMS
- Medium Cost
- High Cost
Based on the access
- Sequential access
- Direct access
- Inverted file structures
Based on the usage
- Online transaction processing (OLTP) DBMS
- Online analytical processing (OLAP) DBMS
- Big data and analytics DBMS
- XML DBMS
- Multimedia DBMS
- GIS DBMS
- Sensor DBMS
- Mobile DBMS
- Open source DBMS
Also Read: Explained Types and Classifications of DBMS
Applications of DBMS
Due to advancements in Database Management System, the companies are getting more and more from their work because they keep all the records of their data. Further, it makes easier to search all the information and records regarding any people or products that help to work efficiently and effectively. Here, we are sharing a few applications and uses of Database Management System (DBMS):
- Railway Reservation System: It is required to keep a record of booking of tickets, departure of the train and the status of arrival. Also, when any train is not on time, then people get to know about the same from the updates in the database.
- Library Management System: There are umpteen numbers of books in the library and it is hard to keep a record of all the books in a register or a copy. So, DBMS is necessary to keep all the book records, issue dates, name of the books, author and maintain the records of all the available books.
- Banking: We can do loads of transactions daily without the commute to the banks. How banking becomes easy by sitting at home? The only reason behind this is the usage of databases and it manages all the data of the customers over the database.
- Educational Institutions:All the examinations done over the web and the data related to the students maintained over the internet with the help of a database management system. It includes registration details of the student, results, grades and courses available in these educational institutes. All the hectic work can be done online without visiting over there.
- Social Media Websites: We all are using social media platforms and fill the required details. Millions of users daily sign up on social websites such as Facebook, Pinterest and Instagram. All the information related to the users can be stored and maintained with the help of DBMS.
Also Read: Explained applications of DBMS
Advantages of Database Management System
Database management system has many advantages and they are like:
- In DBMS, the redundancy problem can be solved
- Has a very high security level
- Presence of referential integrity
- Support multiple users
- Independency of data
- Avoidance of inconsistency
- Shared data
- Enforcement of standards
- Prefer to solve enterprise requirement than individual requirement
- Any unauthorized access is restricted
- Provide backup of data
- Recovery of data
- Affordable cost of manufacturing and developing
- Control on concurrency
- Can develop data models
So, because of such advantages and parameters to overcome the disadvantages this has become a worldwide phenomenon in all the organizations by solving their issues and being a part in making profit.
Also Read: Explained 20 Advantages of DBMS
Disadvantages of Database Management System
Along with the advantages we have some disadvantages to everything and likewise it is to this and the disadvantages are as follows:
- Complexity is a parameter of it because when the internal structure is observed it is very complex.
- Size becomes an issue because in some databases have large size.
- Performance may not run as fast as desired.
- Impact of failure is higher i.e. it makes damage to many parts of the system.
- Some DBMS have unaffordable prices.
- The requirement of the additional hardware increases cost.
- Also have the cost of conversion.
Also Read: Explained 9 Disadvantages of DBMS
Why and when not to use a DBMS system?
There are some times when one needs not to use a DBMS system such as:
- It requires high investment.
- The requirement of DBMS is not a necessity.
- The access to the multi-user is not provided.
- If the database is not efficient to handle the complexities of the data.
- When it does not fulfil the real-time requirements for some application programs due to the overhead embedded systems.
- When it increases the data redundancy.
- If it does not provide the security and privacy to the data which is required.
Best DBMS Books
Here are the top three books for studying Database Management books that will be helpful and enhance your knowledge related to the storing and management of data. The books are listed below:
- Fundamentals of Database Systems by Ramez Elmasri.
- Database System Concepts by Silberschatz, Sudarshan and Korth.
- Database Management Systems by Raghu Ramakrishnan and Johannes Gehrke.
These books are also preferred if one wants to establish their career in the field of Database Management System.