JavaScript Example:

-- Create the database
                CREATE DATABASE IF NOT EXISTS companDB;
                USE companDB;
                
                CREATE TABLE employee_salary (
                  emp_id INT AUTO_INCREMENT PRIMARY KEY,
                  name VARCHAR(100),
                  department VARCHAR(50),
                  salary DECIMAL(10,2),
                  joining_date DATE
                );
                
                INSERT INTO employee_salary (name, department, salary, joining_date)
                VALUES
                ('Alice', 'IT', 75000.00, '2024-01-10'),
                ('Bob', 'HR', 50000.00, '2024-02-15'),
                ('Charlie', 'Finance', 60000.00, '2024-03-20');
                
                SELECT * FROM employee_salary;
                
                ALTER TABLE employee_salary
                ADD COLUMN bonus DECIMAL(10,2) DEFAULT 0.00;
                
                ALTER TABLE employee_salary
                CHANGE COLUMN name full_name VARCHAR(100);
                
                ALTER TABLE employee_salary
                DROP COLUMN bonus;
                
                SELECT * FROM employee_salary;