SQL JOINS AND WINDOW FUNCTIONS WITH CASE EXAMPLE

SQL JOINS When working with relational databases, data is often split across multiple tables. SQL Joins is used to combine data from two or more tables based on related column into one result. It helps in: Matching records using related columns. Retrieving connected data from multiple tables. Improving data analysis by combining related information. Types of SQL Joins SQL joins are categorized into different types based on how rows from two tables are matched and combined. For this article, we will use two tables. i.e STUDENT TABLE and COURSE TABLE For Student table , we create the table first, then we Insert values as shown below: CREATE TABLE Students ( Student_ID INT PRIMARY KEY, First_name VARCHAR(50) NOT NULL, Last_name VARCHAR(50) NOT NULL, Gender CHAR(1), Email VARCHAR(100) UNIQUE ); INSERT INTO Students (Student_ID,First_name, Last_name, Email, Gender) VALUES (201,'Alice', 'Johnson', 'alice.j@university.com', 'F'), (202,'Robert', 'Smith', 'rob.smith@college.edu', 'M'), (203,'El