SQL3 查找当前薪水详情以及部门编号dept_no
select s.*, d.dept_no
from salaries s join dept_manager d on s.emp_no = d.emp_no
where d.to_date = '9999-01-01' and s.to_date = '9999-01-01';
select s.*, d.dept_no
from salaries s join dept_manager d on s.emp_no = d.emp_no
where d.to_date = '9999-01-01' and s.to_date = '9999-01-01';