text: DROP DATABASE IF EXISTS employee_trackerdb;
  CREATE DATABASE employee_trackerdb;
  USE employee_trackerdb;
  
  CREATE TABLE department (
      id INT AUTO_INCREMENT PRIMARY KEY,
      name VARCHAR(30)
  );
  
  CREATE TABLE role (
      id INT AUTO_INCREMENT PRIMARY KEY,
      title VARCHAR(30),
      salary DECIMAL,
      department_id INT,
      FOREIGN KEY (department_id) REFERENCES department(id)
  );
  
  CREATE TABLE employee (
      id INT AUTO_INCREMENT PRIMARY KEY,
      first_name VARCHAR(30),
      last_name VARCHAR(30),
      role_id INT,
      manager_id INT,
      FOREIGN KEY (role_id) REFERENCES role(id),
      FOREIGN KEY (manager_id) REFERENCES employee(id)
  );