text: DROP DATABASE IF EXISTS companyDB;
  
  CREATE DATABASE companyDB;
  
  USE companyDB;
  
  CREATE TABLE department (
  	id INT UNSIGNED AUTO_INCREMENT PRIMARY KEY,
      name VARCHAR(30) NOT NULL,
      PRIMARY KEY (id)
  );
  
  CREATE TABLE role (
  	id INT INT UNSIGNED AUTO_INCREMENT PRIMARY KEY,,
      title VARCHAR(30) NOT NULL,
      salary DECIMAL (10, 2) NOT NULL,
      department_id INT NOT NULL,
      PRIMARY KEY (id)
  );
  
  CREATE TABLE employee (
  	id INTINT UNSIGNED AUTO_INCREMENT PRIMARY KEY,,
      first_name VARCHAR(30) NOT NULL,
      last_name VARCHAR(30) NOT NULL,
      role_id INT NOT NULL,
      manager_id INT,
      PRIMARY KEY (id)
  );
  
  use companyDB;
  INSERT INTO department
      (name)
  VALUES
      ('Sales'),
      ('Engineering'),
      ('Finance'),
      ('Legal');
  INSERT INTO role
      (title, salary, department_id)
  VALUES
      ('Sales Lead', 100000, 1),
      ('Salesperson', 80000, 1),
      ('Lead Engineer', 150000, 2),
      ('Software Engineer', 120000, 2),
      ('Account Manager', 160000, 3),
      ('Accountant', 125000, 3),
      ('Legal Team Lead', 250000, 4),
      ('Lawyer', 190000, 4);
  INSERT INTO employee
      (first_name, last_name, role_id, manager_id)
  VALUES
      ('John', 'Doe', 1, NULL),
      ('Mike', 'Chan', 2, 1),
      ('Ashley', 'Rodriguez', 3, NULL),
      ('Kevin', 'Tupik', 4, 3),
      ('Kunal', 'Singh', 5, NULL),
      ('Malia', 'Brown', 6, 5),
      ('Sarah', 'Lourd', 7, NULL),
      ('Tom', 'Allen', 8, 7);