Database Management System Tutorial(DBMS): Introduction

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Introduction

A Database Management System (DBMS) is a software system that is designed to manage and organize data in a structured manner. It allows users to create, modify, and query a database, as well as manage the security and access controls for that database.

A database management system (DBMS) is system software for creating and managing databases. A DBMS makes it possible for end users to create, protect, read, update and delete data in a database. The most prevalent type of data management platform, the DBMS essentially serves as an interface between databases and users or application programs, ensuring that data is consistently organized and remains easily accessible.

Databases and database technology have a major impact on the growing use of computers. It Is fair to say that databases play a critical role in almost all areas where computers are used, including business, electronic commerce, engineering, medicine, genetics, law, education, and library science.

What is Data?

Data is nothing but facts and statistics stored or free flowing over a network, generally it’s raw and unprocessed. For example: When you visit any website, they might store you IP address, that is data, in return they might add a cookie in your browser, marking you that you visited the website, that is data, your name, it’s data, your age, it’s data.

Data becomes information when it is processed, turning it into something meaningful. Like, based on the cookie data saved on user’s browser, if a website can analyse that generally men of age 20-25 visit us more, that is information, derived from the data collected.

What is Database?

A Database is a collection of related data organised in a way that data can be easily accessed, managed and updated. Database can be software based or hardware based, with one sole purpose, storing data.

During early computer days, data was collected and stored on tapes, which were mostly write-only, which means once data is stored on it, it can never be read again. They were slow and bulky, and soon computer scientists realised that they needed a better solution to this problem.

Functions of Database

1.          Store, retrieve, and update data.
2.          Provide integrity services to enforce database.
3.         Provide a user-accessible catalog of data descriptions.
4.          Control concurrent processing.
5.          Support logical transactions.
6.          Recover form failure.
7.          Interface with communication control programs.
8.         Provide utility services.

How does User Interacts with Database?

1. User interacts with DBMS by an interface generally this interface is a command user interface.    You may also say it as a tool which is used by the user to perform the several operation like creating a database, storing data in the database, updating data, creating tables in the, security.
2. User gives the commands on this interface in order to perform these operations.
3.  Normally SQL Structured Query Language commands are used on most of the database.
4.  DBMS gives the facility to the user to protect the databases used in database management system. It also provide a way so that multiple user can use the same database. Some widely used  DBMS in industry are MySql, Oracle, SQL Server , IBM DB2.

What is Database System?

Database is collection of data which is related by some aspect. Data is collection of facts and figures which can be processed to produce information. Name of a student, age, class and her subjects can be counted as data for recording purposes.

A database management system stores data, in such a way which is easier to retrieve, manipulate and helps to produce information.

Mostly data represents recordable facts. Data aids in producing information which is based on facts. For example, if we have data about marks obtained by all students, we can then conclude about toppers and average marks etc.

Database Management System (DBMS)

A database management system (DBMS) is a collection of programs enabling users to create and maintain a database. More specifically, the DBMS is a general-purpose software system that facilitates the processes of defining, constructing, manipulating, and sharing databases among various users and applications.

1.  Defining a database involves specifying the data types, structures, and constraints of the data to be stored in the database. The database definition or descriptive information is stored by the DBMS in the form of a database catalog or dictionary; it is called meta-data.
2.       Constructing the database is the process of storing the data on some storage medium that is controlled by the DBMS.
3. Manipulating a database includes functions such as querying the database to retrieve specific data, updating the database to reflect changes in the mini world, and generating reports from the data.
4.  Sharing a database allows multiple users and programs to access the database simultaneously.

Characteristics of DBMS

The database approach has some very characteristic features which are discussed in detail below:

  ·        Structured and Described Data:

Fundamental feature of the database approach is that the database system does not only contain the data but also the complete definition and description of these data. These descriptions are basically details about the extent, the structure, the type and the format of all data and, additionally, the relationship between the data. This kind of stored data is called metadata (“data about data”).

       ·        Separation of Data and Applications:

Application software does not need any knowledge about the physical data storage like encoding, format, storage place, etc. It only communicates with the management system of a database (DBMS) via a standardized interface with the help of a standardized language like SQL. The access to the data and the metadata is entirely done by the DBMS. In this way all the applications can be totally separated from the data.

      ·        Data Integrity:

Data integrity is a byword for the quality and the reliability of the data of a database system. In a broader sense data integrity includes also the protection of the database from unauthorized access (confidentiality) and unauthorized changes. Data reflect facts of the real world.

      ·        Transactions:

A transaction is a bundle of actions which are done within a database to bring it from one consistent state to a new consistent state. In between the data are inevitable inconsistent. A transaction is atomic what means that it cannot be divided up any further. Within a transaction all or none of the actions need to be carried out. Doing only a part of the actions would lead to an inconsistent database state.

Example: One example of a transaction is the transfer of an amount of money from one bank account to another.

      ·        Data Persistence:

Data persistence means that in a DBMS all data is maintained as long as it is not deleted explicitly. The life span of data needs to be determined directly or indirectly be the user and must not be dependent on system features. Additionally data once stored in a database must not be lost. Changes of a database which are done by a transaction are persistent. When a transaction is finished even a system crash cannot put the data in danger.
   

Why Use DBMS

i)                    To develop software applications In less time.

ii)                  Data independence and efficient use of data.

iii)                For uniform data administration.

iv)                For data integrity and security.

v)                  For concurrent access to data, and data recovery from crashes.

vi)                To use user-friendly declarative query language.

Example of DBMS

These DBMS software provide the facility od creating the database and managing the data in from  tabular form. Let’s us understand  Payroll Management System database.

This database maintains the information about employee of an organization, their monthly salary process. This database contains the following table.

1.          Employee table store data of each employee.
2.          Department Table store data of each department.
3.          Project Table store all data about project
4.          Admin table store the information about administrator login
5.          Salary Table store the information salary and working hrs of the employee
6.          Deduction table store information about leave and other deduction.
7.          In order to handle the data in database we have to create a database and then create the tables in side that database, applying integrity constraints on the table and then insert the data in related table. Once the data is inserted then we can perform various operation on the data which is stored.

Goals of Database Management System (DBMS)

The primary goal of a DBMS is to provide a way to store and retrieve database information that is both convenient and efficient.

•          Manage large bodies of information.
•          Provide convenient and efficient ways to store and access information.
•         Secure information against system failure or tampering.
•       Permit data to be shared among users.

What is DBMS Scope?

People looking to get into the IT industry or want to specialize in a database should know DBMS; there’s a bleak chance of survival. This ever-increasing data will increase the need for DBAs and knowledgeable database people. DBMS surely is the thing that is going to rule the world, as data is the key to all things. Yes, there will be changes in how and where the data is to be stored, but DBMS will remain the same. Not only in the IT are industry but a variety of people using DBMS. Sectors like; Banking, Manufacturing, and Online Bookings (E-Ticketing) are using it. We all have been using the current trending applications, WhatsApp, Instagram, and Snapchat daily, but do we know what goes behind all the interfaces, it’s DBMS!

Why Learn DBMS?

Any organization, be it a bank, manufacturing company, hospital, University, or Government Office, requires a huge amount of data in some form. All such organizations need to collect data, manipulate them and store them for future use. All such types of organizations require data for several purposes, say:

i)                    Preparing Sales Reports

ii)                  Forecasting Sales

iii)                Preparing Accounts Reports

iv)                Getting Medical Histories of Patients

DBMS provides a more efficient, secure, and scalable approach to data management than traditional file-based systems. It ensures data consistency, integrity, and security while enabling data sharing, integration, and analysis. These benefits make DBMS an essential tool for managing and processing data in modern organizations. It is said that data is the oil of the 21^st century. With data being of utmost importance, there is a need to understand the system that helps us store and manage data in a standardized structure.

If you know DBMS, that means you can:

•          Solve real-world problems by connecting them to DBMS relations and entities.
•          Help businesses organize their data more effectively.
•          And do a lot more….

Need of DBMS:

•  Before the advent of DBMS, organizations typically stored information using a “File Processing Systems". Example of such systems is File Handling in High Level Languages like C, Basic and COBOL etc., these systems have major disadvantages to perform the Data Manipulation. So to overcome those drawbacks now we are using the DBMS.

•  Database systems are designed to manage large bodies of information.
• In addition to that the database system must ensure the safety of the information stored, despite system crashes or attempts at unauthorized access. If data are to be shared among several users, the system must avoid possible anomalous results.

Applications of DBMS

DBMS is extensively used in real-time systems due to its adaptability to various use cases. Most popularly it is used in banking, education, transport, tourism, human resource management, manufacturing and e-commerce for storing data of items or users and analyzing insights from it.

Advantages of Database Management System (DBMS)

Using a DBMS to manage data has many advantages:

          1.     Data Independence:
Application programs should be as independent as possible from details of data representation and storage. The DBMS can provide an abstract view of the data to insulate application code from such details.
    2.     Efficient Data Access:
A DBMS utilizes a variety of sophisticated techniques to store and retrieve data efficiently. This feature is especially important if the data is stored on external storage devices.
    3.     Data Integrity and Security:
If data is always accessed through the DBMS, the DBMS can enforce integrity constraints on the data. For example, before inserting salary information for an employee, the DBMS can check that the department budget is not exceeded. Also, the DBMS can enforce access controls that govern what data is visible to different classes of users.
     4.     Concurrent Access and Crash Recovery:
A database system allows several users to access the database concurrently. Answering different questions from different users with the same (base) data is a central aspect of an information system. Such concurrent use of data increases the economy of a system.
An example for concurrent use is the travel database of a bigger travel agency. The employees of different branches can access the database concurrently and book journeys for their clients. Each travel agent sees on his interface if there are still seats available for a specific journey or if it is already fully booked. A DBMS also protects data from failures such as power failures and crashes etc. by the recovery schemes such as backup mechanisms and log files etc.
    5.     Data Administration:
When several users share the data, centralizing the administration of data can offer significant improvements. Experienced professionals, who understand the nature of the data being managed, and how different groups of users use it, can be responsible for organizing the data representation to minimize redundancy and fine-tuning the storage of the data to make retrieval efficient.
    6.     Reduced Application Development Time:
DBMS supports many important functions that are common to many applications accessing data stored in the DBMS. This, in conjunction with the high-level interface to the data, facilitates quick development of applications. Such applications are also likely to be more robust than applications developed from scratch because many important tasks are handled by the DBMS instead of being implemented by the application.

Disadvantages of Database Management System (DBMS)

          1.   Danger of a Overkill:
For small and simple applications for single users a database system is often not advisable.
     2.    Complexity:
A database system creates additional complexity and requirements. The supply and operation of a database management system with several users and databases is quite costly and demanding.
    3.    Qualified Personnel:
`The professional operation of a database system requires appropriately trained staff. Without a qualified database administrator nothing will work for long.
    4.   Costs:
Through the use of a database system new costs are generated for the system itself but also for additional hardware and the more complex handling of the system.
    5.  Lower Efficiency:
A database system is a multi-use software which is often less efficient than specialized software which is produced and optimized exactly for one problem.

Career Opportunity of Learning DBMS

DBMS is a major skill for software engineers and considering the huge demand for understanding and analyzing data, DBMS is a sought-after skill. Here are the few most sought-after opportunities that you can explore with this skill:

Data Architect: Designs and builds intricate data frameworks based on the product requirements.

Data Engineer: Develops database solutions as designed by the data architect.

Database Manager: Maintains the database, normalizing it and preparing it for expansion.

Data Analyst: Evaluates company’s data and taking decisions regarding improving market position.

Data Scientist: Designs and constructs new processes that would improve data mining and data production.

Summary

This article shows that Data is the prime need in today’s technological world. I wouldn’t be wrong in saying that the world functions on data. That’s why arrangement and management of data are a prime need in this world. That’s what a database management system is for. The DBMS essentially serves as an interface between databases and users or application programs, ensuring that data is consistently organized and remains easily accessible. It’s Characteristics, Needs, Usages, Applications, Goals, Carrier Opportunities, Definition of DBMS, Advantages and Disadvantages of DBMS are discussed in this article.