text: -- Select the employee number, last name, first name, sex, and salary of all employees, ordered by employee number
  SELECT employees.emp_no,
  		employees.last_name,
  		employees.first_name,
  		employees.gender,
  		salaries.salary
  FROM employees
  INNER JOIN salaries ON employees.emp_no = salaries.emp_no
  ;
  -- Select the first name, last name, and hiring date for all employees hired in 1986 
  SELECT first_name,
  		last_name,
  		hire_date
  FROM employees
  WHERE hire_date >= '1986-01-01' and hire_date <= '1986-12-31'
  ;
  -- Select the department number, department name, employee number, last name, and first name of all managers of each department
  SELECT dept_manager.dept_no,
  		departments.dept_name,
  		dept_manager.emp_no,
  		employees.last_name,
  		employees.first_name
  FROM dept_manager
  INNER JOIN departments on dept_manager.dept_no = departments.dept_no
  INNER JOIN employees on employees.emp_no = dept_manager.emp_no
  ;
  -- Select the employee number, last name, first name, and department of each employee, ordered by employee number
  SELECT employees.emp_no,
  		employees.last_name,
  		employees.first_name,
  		departments.dept_name
  FROM employees
  INNER JOIN dept_emp ON dept_emp.emp_no = employees.emp_no
  INNER JOIN departments ON departments.dept_no = dept_emp.dept_no
  ;
  -- Select first name, last name, birth date, and sex of all employees whose first name is "Hercules" and last name begins with a "B"
  SELECT first_name,
  		last_name,
  		gender
  FROM employees
  WHERE first_name = 'Hercules' and last_name LIKE 'B%'
  ;
  -- Select employee number, last name, first name, and department name of all employees in the Sales department, ordered by employee number
  SELECT employees.emp_no,
  		employees.last_name,
  		employees.first_name,
  		departments.dept_name
  FROM employees
  INNER JOIN dept_emp ON dept_emp.emp_no = employees.emp_no
  INNER JOIN departments ON departments.dept_no = dept_emp.dept_no
  WHERE departments.dept_name = 'Sales'
  ORDER BY emp_no
  ;
  -- Select employee number, last name, first name, and department name of all employees in the 'Sales' OR the 'Development' department, ordered by employee number
  SELECT employees.emp_no,
  		employees.last_name,
  		employees.first_name,
  		departments.dept_name
  FROM employees
  INNER JOIN dept_emp ON dept_emp.emp_no = employees.emp_no
  INNER JOIN departments ON departments.dept_no = dept_emp.dept_no
  WHERE departments.dept_name = 'Sales' OR departments.dept_name = 'Development'
  ORDER BY emp_no
  ;
  -- Count the number of employees, grouped by last name
  SELECT employees.last_name, COUNT(employees.emp_no)
  FROM employees 
  GROUP BY employees.last_name
  ;
  