text: SELECT * FROM department;
  SELECT * FROM role;
  SELECT * FROM employee;
  
  --Department--
  
  INSERT INTO department (id, name)
  VALUES (1, "Sales");
  INSERT INTO department (id, name)
  VALUES (2, "Engineering");
  INSERT INTO department (id, name)
  VALUES (3, "Finance");
  INSERT INTO department (id, name)
  VALUES (4, "Legal");
  INSERT INTO department (id, name)
  VALUES (5, "Manager");
  
  --Role--
  INSERT INTO role (id, title, salary, department_id)
  VALUES (1, "Sales Lead", 55000, 1);
  INSERT INTO role (id, title, salary, department_id)
  VALUES (2, "Salesperson", 35000, 1);
  INSERT INTO role (id, title, salary, department_id)
  VALUES (3, "Lead Engineer", 65000, 2);
  INSERT INTO role (id, title, salary, department_id)
  VALUES (4, "Accountant", 50000, 3);
  INSERT INTO role (id, title, salary, department_id)
  VALUES (5, "Legal Team Lead", 56000, 4);
  INSERT INTO role (id, title, salary, department_id)
  VALUES (6, "Manager", 65000, 5);
  
  --Employee--
  SET FOREIGN_KEY_CHECKS=0;
  INSERT INTO employee (id, first_name, last_name, role_id, manager_id)
  values (6, "Dokja", "Kim", 6, null); 
  INSERT INTO employee (id, first_name, last_name, role_id, manager_id)
  values (3, "Sooyoung", "Han", 4, 6);
  INSERT INTO employee (id, first_name, last_name, role_id, manager_id)
  values (5, "Joonghyuk", "Yoo", 3, 6);
  INSERT INTO employee (id, first_name, last_name, role_id, manager_id)
  values (2, "Seolhwa", "Lee", 1, 6);
  INSERT INTO employee (id, first_name, last_name, role_id, manager_id)
  values (1, "Hyungsung", "Lee", 2, 1);
  INSERT INTO employee (id, first_name, last_name, role_id, manager_id)
  values (4, "Sangah", "Yoo", 5, 6);
  SET FOREIGN_KEY_CHECKS=1;