text: DROP DATABASE IF EXISTS employeeDB;
  CREATE DATABASE employeeDB;
  USE employeeDB;
  
  CREATE TABLE department (
      id INT NOT NULL AUTO_INCREMENT,
      name VARCHAR(30) NOT NULL,
      PRIMARY KEY (id)
  );
  
  CREATE TABLE role (
      id INT NOT NULL AUTO_INCREMENT,
      title VARCHAR(30) NOT NULL,
      salary VARCHAR(30) NOT NULL,
      department_id INT,
      PRIMARY KEY (id),
      CONSTRAINT fk_department FOREIGN KEY (department_id) REFERENCES department(id)
  );
  
  CREATE TABLE employee (
      id INT NOT NULL AUTO_INCREMENT,
      first_name VARCHAR(30) NOT NULL,
      last_name VARCHAR(30) NOT NULL,
      role_id INT,
      manager_id INT,
      PRIMARY KEY (id),
      CONSTRAINT fk_role FOREIGN KEY (role_id) REFERENCES role(id),
      CONSTRAINT fk_employee_manager FOREIGN KEY (manager_id) REFERENCES employee(id)
  );