Lec-2: Introduction to DBMS (Database Management System) With Real life examples | What is DBMS
Introduction to DBMS
Importance of DBMS
- The lecture introduces Database Management Systems (DBMS) as a crucial subject for competitive exams like GATE and UGC NET, especially for B.Tech and BCA students.
- Over the past 6-7 years, the relevance of DBMS has increased significantly in interviews, with major companies focusing on database-related questions.
- Top Fortune 50 companies such as Facebook, Google, and Amazon rely heavily on databases for their operations.
Understanding Database Systems
- A database system consists of two main components: the database itself and the DBMS that manages it.
- The definition of a database is presented as a collection of related data, emphasizing its organized nature.
Characteristics of Databases
Related Data Concept
- Related data refers to information that is logically connected; for example, IRCTC's database contains train schedules and passenger information but not unrelated data like passport details.
Types of Data Structures
- Databases can be categorized into structured, semi-structured, and unstructured types. However, structured data is primarily focused on in this discussion.
- Structured data can be stored in specific formats or structures (e.g., RDBMS), while unstructured data lacks a defined format.
Functions of DBMS
Operations Performed by Users
- Users interact with databases through various operations such as insertion (adding new data), deletion (removing old data), and updating existing records.
Role of DBMS
- A Database Management System facilitates these operations by providing an interface that allows users to manage their data efficiently without needing to know where it is physically stored.
Examples of Popular DBMS
Different Versions Available
- Various companies have developed different versions of popular DBMS software:
- Microsoft SQL Server (multiple versions)
- Oracle SQL Server (various releases)
- MySQL (owned by Oracle)
- IBM's DB2
Understanding Relational Database Management Systems (RDBMS)
What is a Relation?
- A relation refers to a table format for storing structured data, similar to an Excel file with columns and rows.
- The most common method of storing data is in relational form, necessitating a management system that supports this structure.
Data Access and Management
- When accessing data, such as checking train information on IRCTC, the results are displayed in a tabular format with specific columns like train number and departure time.
- RDBMS focuses on structured data storage and retrieval, which is crucial for various competitive exams like GATE and UGC NET.
Introduction to DBMS and RDBMS
- A Database Management System (DBMS) is essential for managing relations; thus, the term RDBMS (Relational Database Management System) was introduced.
- RDBMS allows operations such as insertions, deletions, and updates specifically on relations or tables.
Understanding Unstructured Data
- Unstructured data lacks a predefined format for storage; examples include photos and videos that do not conform to any specific structure.
- Unlike structured data stored in tables, unstructured data can vary widely in format within web pages.
Current Trends in Data Storage
- While structured data remains relevant, approximately 90% of global data today is unstructured.