text: DROP DATABASE IF EXISTS empDB1;
  DROP TABLE IF EXISTS department;
  DROP TABLE IF EXISTS role;
  DROP TABLE IF EXISTS employee;
  
  CREATE DATABASE empDB1;
  
  USE empDB1;
  
  CREATE TABLE department (
      id INT AUTO_INCREMENT,
      name VARCHAR(30) NOT NULL,
      PRIMARY KEY(id)
  );
  
  CREATE TABLE role (
      id INT AUTO_INCREMENT,
      title VARCHAR(30) NOT NULL,
      salary DECIMAL (8,2) NOT NULL,
      department_id INT,
      PRIMARY KEY(id)
      FOREIGN KEY (department_id) REFERENCES department(id)
  );
  
  CREATE TABLE employee (
      id INT AUTO_INCREMENT,
      first_name VARCHAR(30) NOT NULL,
      last_name VARCHAR(30) NOT NULL,
      role_id INT,
      manager_id INT,
      PRIMARY KEY(id)
  
      FOREIGN KEY (role_id) REFERENCES role(id),
      FOREIGN KEY (manager_id) REFERENCES employee(id)
  );