Lec-2: Introduction to DBMS (Database Management System) With Real life examples | What is DBMS

Database Management Systems (DBMS) are crucial for students in B.Tech and BCA programs, especially given their rising importance in competitive exams like GATE and UGC NET. Over the past 6-7 years, there has been a significant increase in interview questions related to DBMS due to its central role in major companies such as Facebook, Google, and Amazon. These organizations rely heavily on databases for their operations; hence understanding DBMS is essential not only academically but also professionally.

A database system consists of two main components: the database itself and the Database Management System (DBMS). Examples include Facebook, Indian Railways' IRCTC, and Flipkart, each utilizing their own unique database systems to manage data effectively. Understanding this distinction is crucial for grasping how various organizations handle information.

A database is fundamentally a collection of related data. For example, the Indian Railways' IRCTC has a vast database containing information about train schedules and passenger details. This data must be relevant to its purpose; for instance, it cannot mix with unrelated databases like those of passport holders. Databases can be categorized into structured, semi-structured, and unstructured types, but understanding these distinctions isn't always crucial for basic knowledge.

Structured data refers to information organized in a defined format, such as databases that follow specific schemas. Examples include Indian railways and university data, which have clear structures for storing and retrieving information. In contrast, unstructured data lacks this organization. The primary system used for managing structured data is the Relational Database Management System (RDBMS), which facilitates efficient storage and access.

A database management system (DBMS) is essential for managing large amounts of data stored on servers and hard drives. Users need to perform operations such as inserting, updating, or deleting data efficiently. Regardless of where the data is physically located—like accessing train reservations from different cities—the DBMS allows users to interact with it seamlessly without concern for its location. Various companies have developed their own versions of DBMS software, including Microsoft SQL Server and Oracle's multiple iterations over the years.

Structured data is organized in a relational format, typically represented as tables with rows and columns, similar to an Excel spreadsheet. This structure allows for efficient storage and management of data through systems designed specifically for this purpose. A Relational Database Management System (RDBMS) facilitates operations such as inserting, deleting, or updating records within these structured formats. Understanding how to manage structured data is crucial not only in academic settings like B.Tech but also in competitive exams where questions on RDBMS frequently arise.

Unstructured data lacks a predefined format, making it difficult to store systematically. It primarily consists of photos, videos, and web page content that can appear in any order or structure. In contrast, structured data is organized into tables with specific formats for easy management and retrieval. Currently, about 90% of the world's data is unstructured; however, technologies like big data and Hadoop focus on this type while traditional RDBMS systems work exclusively with structured data.