text: DROP DATABASE IF EXISTS employeetracker_db;
  CREATE database employeetracker_db;
  USE employeetracker_db;
  
  CREATE TABLE employee (
  	id INT NOT NULL AUTO_INCREMENT,
  	first_name VARCHAR(30),
      last_name VARCHAR(30),
      role_id INT,
      manager_id INT,
      PRIMARY KEY(id)
  );
  
  CREATE TABLE department (
  	id INT NOT NULL AUTO_INCREMENT,
      department_name VARCHAR (30),
      PRIMARY KEY(id)
  );
  
  CREATE TABLE roles (
  	id INT NOT NULL AUTO_INCREMENT,
      title VARCHAR(30),
  	salary INT,
      department_id INT,
      PRIMARY KEY(id)
  );