1.查询员工12个月的工资总和，并起别名为ANNUAL SALARY
SELECT last_name,salary
FROM employees
WHERE salary NOT between 5000 AND 12000;
# WHERE salary<5000 || salary>120000;
2.选择在20或50号部门工作的员工姓名和部门号
SELECT last_name, department_id
FROM employees
WHERE department_id IN (20,50);
# WHERE department_id = 20 || department_id = 50;
