text: DROP DATABASE IF EXISTS employee_trackerDB;
  
  CREATE DATABASE employee_trackerDB;
  
  USE employee_trackerDB;
  
  CREATE TABLE departments (
      id INT AUTO_INCREMENT NOT NULL,
      name VARCHAR(30) NOT NULL,
      PRIMARY KEY (id)
  );
  
  CREATE TABLE roles (
      id INT AUTO_INCREMENT NOT NULL,
      title VARCHAR(30) NOT NULL,
      salary DECIMAL(10,2) NOT NULL,
      department_id INT NOT NULL,
      PRIMARY KEY (id)
  );
  
  CREATE TABLE employees (
      id INT AUTO_INCREMENT NOT NULL,
      first_name VARCHAR(30) NOT NULL,
      last_name VARCHAR(30) NOT NULL,
      role_id INT NOT NULL,
      manager_id INT,
      PRIMARY KEY (id)
  );