Introduction to RDBMS 🗃️

Krishna Lodha

What is RDBMS?

A Relational Database Management System (RDBMS) is software designed to store, manage, and retrieve data in a structured format using tables.

Example Table

• Storing student information in table named student

id	Name	Age	Gender	Class
1	John	18	Male	10
2	Jane	18	Female	10
3	Mary	19	Female	10
4	David	20	Male	10

Example Relational Table

• Storing students marks in table as student_marks

student_id	subject	marks
1	Maths	80
1	English	90
2	Maths	70
2	English	80
3	Maths	90
3	English	80

Why use RDBMS?

• Efficient data storage and retrieval.
• Easy to maintain and scale.
• Supports large volumes of data.
• Ensures data integrity through constraints.
• Handles complex queries with SQL.

Core Components of RDBMS

• Tables: Structure for storing data.
• Primary Key: Unique identifier for each record.
• Foreign Key: Establishes relationships between tables.
• Indexes: Speeds up data retrieval.
• Schema: Defines database structure.

ACID Properties of RDBMS

• Atomicity: Transactions are all or nothing.
• Consistency: Always maintains valid states.
• Isolation: Transactions don’t interfere with each other.
• Durability: Changes persist after transaction completion.

Common RDBMS Software

• Open-source: MySQL, PostgreSQL, SQLite.
• Enterprise: Oracle Database, Microsoft SQL Server.
• Cloud: Amazon RDS, Google Cloud SQL, Azure SQL Database.

Demo Time!

• Let’s create a table in PostgreSQL.
• Let’s insert some data into the table.
• Let’s retrieve the data from the table.

Create a table in PostgreSQL

CREATE TABLE student (
  id SERIAL PRIMARY KEY,
  name VARCHAR(50),
  age INT,
  gender VARCHAR(10),
  class INT
);

create

Insert some data into the table

INSERT INTO student (name, age, gender, class)
VALUES ('John', 18, 'Male', 10),
       ('Jane', 18, 'Female', 10),
       ('Mary', 19, 'Female', 10),
       ('David', 20, 'Male', 10);

insert

Retrieve the data from the table

SELECT * FROM student;

get