text: DROP DATABASE IF EXISTS employee_trackerDB;
  
  create database employee_trackerDB;
  
  use employee_trackerDB;
  
  create table department(
  	id int not null auto_increment,
      name varchar(60),
      primary key (id)
  );
  
  create table role(
  	id int not null auto_increment,
      title varchar(60),
      salary decimal(10,2),
      department_id int,
      primary key (id),
      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),
      FOREIGN KEY (role_id) REFERENCES role(id),
      FOREIGN KEY (manager_id) REFERENCES employee(id)
  );