What is Database | Definition, Features, Working

As the name suggests, a database is an organized collection of logically related data or information. In other words, a database is a storage area where we can store all related data and easily accessed, managed, and updated them.

Let us take some real-time examples of database (storage) to understand the concept of database. An example of logical database we carry with us all the time is our brain.

The brain stores thoughts, ideas, and everything we learn or experience, and it relates them to each other. We can retrieve, modify, or even forget these stored ideas and thoughts whenever needed at any time.

A real-life example of a physical database is a grain warehouse. During the harvest season, grains or pulses are stored in the warehouse and used later as required.

When we process these grains or pulses, we obtain products such as flour or sprouts, which we further use to prepare food. Any grains or pulses which we find useless we remove from the warehouse and replace (i.e. update) with fresh stock.

Another real-life example of a database is a child’s school bag. It is a stationary database that contains entities such as notebooks, textbooks, a geometry box, and a compass box. The notebook entity consists of different notebooks for various subjects. The textbook entity contains textbooks for different subjects.

The compass box entity holds items like pens, pencils, erasers, sharpeners, and rulers, while the geometry box entity includes common mathematical tools. Each entity is organized logically, and hence, it is a database. Look at the below figure.

Real-life example of Database.

Definition of Database


A database can be defined as a structured collection of data that is stored and managed electronically. It can store any type of data, such as numbers, words, images, videos, and files. We use a Database Management System (DBMS) software to store and manage data in the database electronically.


Some of the commonly used database software is as follows:

  • Oracle
  • MySQL
  • SQL Server
  • MongoDB
  • Microsoft Access
  • FileMaker Pro
  • dBase
  • OpenOffice Base
  • PostgreSQL
  • Sybase

These software tools allow users to store, retrieve, and manipulate data efficiently. The main purpose of a database is to handle large volumes of information by storing, retrieving, and managing data effectively. As a result, databases are considered the backbone of modern applications, supporting businesses, organizations, and systems across various industries.

Why Do We Need a Database?


In today’s world, we are using a database in almost everywhere. This is because the database is the best way to store, manage, and retrieve the data. It makes data persistent, secure, and shareable. Let’s understand with some examples of real world application why do we need a database?

  • Schools: Schools use databases to store and manage information about students, teachers, and books in the library.
  • Shopping Complexes: When you go shopping, then the shopping complex and retail stores use the database to maintain details of stock details, track sales, and manage customer information.
  • Companies: Companies use databases to track the information of their employees.
  • Hospitals: Hospitals use databases to store patient information, medical records, and appointment schedules.
  • Banking: Banks utilize databases to manage customer accounts, transactions, and loan details securely.
  • E-commerce Websites: Online shopping platforms like Amazon or eBay use databases to store product information, order history, and customer preferences.
  • Social Media Platforms: Websites like Facebook, Instagram, and Twitter use databases to manage user profiles, posts, and interactions.
  • Airlines: Airlines rely on databases to manage flight schedules, ticket bookings, and passenger details.
  • Government Agencies: Governments use databases to maintain records for taxation, voter registrations, and public welfare schemes.
  • Telecommunication Companies: Telecom providers use databases to manage customer subscriptions, call records, and billing information.

In almost every field, we are directly or indirectly using a database. The above real-time examples exhibit how databases have become an integral part of modern systems and services.

Why is a Database Important?


Imagine you are running a business without knowing who your customers are, what products you are selling, who is working for you, who owes you money, and to whom you owe money. Every business needs to keep this type of data and much more. Just as important, this data must be readily available to decision-makers when needed.

This is why, databases play a significant role in managing and organizing data for businesses or organizations to survive and prosper. Here’s some key points why databases are essential:

1. Efficient Data Management: Databases provide a structured way to store and organize a massive amount of data or information. With database, we can easily access, retrieve, update, and delete data records when we need.

2. Scalability: Databases can efficiently scale to handle millions or even billions of records, which would be impossible to manage manually. This makes them indispensable for industries like e-commerce, banking, and social media.

3. Data Integrity: By applying rules and constraints (conditions), databases ensure data consistency and accuracy even as data grows or changes. This is especially important for applications such as hospital patient records and financial transactions.

4. Data Security: Modern databases provide robust security to protect sensitive information by implementing user authentication, access control, and compliance with privacy regulations. This is essential for industries such as banking and telecommunications.

5. Data Analytics and Decision-Making: Advanced databases support analytics tools to identify patterns, trends, and predictions, which enable organizations to make data-driven decisions. For example, businesses analyze customer data to improve their services, and governments use databases for public welfare programs.

6. Data Sharing: Once a database is created, it can be shared by multiple users. Therefore, a database is required to share data across multiple applications.

7. Flexibility: A database provides flexibility because we can connect it to different front-end applications as needed.

Key Features of a Database


The main features of a database are as follows:

  • A database has the ability to store a large amount of structured data, making it easy to retrieve, update, and manage. It organizes the data into tables, rows, and columns.
  • Databases help to ensure data accuracy and consistency through constraints, rules, and validation. This includes primary keys, foreign keys, and unique constraints to maintain data integrity.
  • They provide several mechanisms to protect data from unauthorized access. This is achieved by implementing user authentication, encryption, and access control policies.
  • A database allows users to query and retrieve specific data using query languages like SQL (Structured Query Language). This supports filtering, sorting, and complex searches.
  • Databases allow users to establish relationships between different data tables, such as one-to-one, one-to-many, many-to-one, and many-to-many relationship.
  • With a database, multiple users can access and modify data simultaneously. This is managed through locking mechanisms, transaction isolation, and concurrency protocols to ensure data consistency.
  • Database helps to minimize data redundancy (i.e. duplication) through normalization techniques, which ensures that data is stored in an efficient and organized way.
  • A database can handle growing amounts of data and increasing numbers of users through scalability. It provides vertical and horizontal scaling options to manage higher loads.
  • Databases provide mechanisms for data backup and recovery to protect against data loss. These mechanisms include regular backups and transaction logs so that data can be restored in case of hardware failures, software issues, or human errors.

How is Database Organized?


Data itself needs to be stored in a standardized way so that database can efficiently retrieve and manipulate it. There are several levels at which you can examine the storage of data. Some key elements involved in this process are:

  • Database File
  • Table
  • Record
  • Field
  • Data Type

The hierarchy of database is shown in the below diagram.

Database hierarchy diagram

1. Database File: A database file is the physical storage unit where all the data of a database is stored. It acts as a container that holds the tables and other database objects, such as forms, queries, and reports. A database file is stored on the computer hard drive, SSD, or cloud storage.

2. Tables: A database is a collection of related tables. A table is a fundamental building block of any database where the related data is organized and stored in a structured format. It consists of rows and columns, much like a spreadsheet.

Each table represents a specific entity or information of one type of item. For example, a School is a database that may contain student’s details such as name, roll number, date of birth, address, and phone number.

3. Records: A record is a collection of data values or information related to one entity. It is arranged horizontally to make complete information. A table may contain a number of records. Record of a table is also known as row, or entity. For example, in a student database table, each row would contain the information related to one student.

4. Fields: A field is an individual sub-component of one record. It is vertically arranged and store the data value of the same type. A table usually contains multiple fields. Field in a table is also known as column or attribute. For example, the fields of a student table include RollNo, Name, Date of Birth, Address, and Phone No.

5. Data Value: Data value is the value that may be text, number, date, audio, video, image, etc. It is the smallest unit of a database which is formed by intersection of a row and a column. Vertical part represents the column and makes a collection of the same type of data. Horizontal part represents the row and makes one complete information of an entity.

Let us take an example of student table with the following data in a relational database School, as shown below:

Student Database Table

In the above student table, there are 6 rows (records) and 5 columns (fields). If a new student joins a school, the complete information of a new student will add in the form of a record/row. The fields like Rollno will store only integers, Name will store only text, and Date of Birth will store only date.

Working of a Database


Database is created to handle a large amount of data by allowing the user to input, store, retrieve, and manage the information efficiently. It is a centralized location which provides an easy way to access the data for multiple users.

Instead of maintaining separate copies of a data file, a database enables multiple users to access the same data simultaneously. In other words, the database does not create separate copies of a particular data file. Instead, multiple users can access the same data at the same time.

Working of a database

As the diagram shown in the above, the DBMS works as an interface between the user and the centralized database. First, the user sends a request or a query to a DBMS. The DNMS then searches the requested query in the centralized database.

If the relevant data is obtained, it is retrieved and forwarded to the user. If the output does not completely match with the requirement of the user, a rollback (again search) is done and again search process is performed until the desired output is obtained.

Advantages of Databases


Some of the main advantages of the databases are as follows:

1. Reduce Data Redundancy: Data Redundancy means storing the same data multiple times in the system. This may lead to several problems. A Database Management System (DBMS) reduces redundancy by interlinking data in tables through common columns to avoid duplicate entries. In addition, data constraints are applied to store data based on predefined conditions, ensuring accuracy and consistency.

2. Data Sharing: Data sharing means sharing single piece of data among different users. The data stored in the database can be shared among multiple users or application programs in real time.

3. Data Integrity: This means that the data stored in the database is accurate, reliable, and consistent. Integrity means constraints (i.e. consistency rules) that the database system must not violate. Data integrity constraints validate the data so that the correct data is stored in the database. This is also very important because the data is accessed and used by multiple users.

4. Data Security: The DBMS offers data security, which allows only authorized users to access the database. The Database Administrator (DBA) defines usernames and passwords to authenticate and identify authorized users, preventing unauthorized access.

5. Providing Data Backup and Recovery: A DBMS provides the data backup and recovery features so that the user can maintain data backup on weekly, fortnightly, or scheduled basis. This is highly helpful when the data loss occurs due to the system failure. The data recovery process can be easily carried out to recover the loss data.

6. Improved Data Quality: The database system provides several tools and processes to improve the data quality.

Disadvantages of Databases


We know that there are many of advantages of using databases, but also have some minor disadvantages of it. These disadvantages are as follows:

1. Cost of Hardware and Software: The use of database system increases additional new cost of hardware and software, which can be expensive.

2. Complexity: A database system creates additional complexity and requirements for skilled professionals to manage and maintain them effectively.

3. Database Failures: If the databases become corrupted due to the failure of power, hardware malfunctions, or software bugs, your valuable data may be lost and the system will stop working.

4. Lower Efficiency: A database system is a multi-user software, which may become less efficient when handling large amounts of data and multiple concurrent users if queries are not properly optimized.

5. Security Risks: Although databases provide security features, they are still vulnerable to cyberattacks, data breaches, and unauthorized access, if not properly secured.