复习 limit x,y x for 偏移量，跳过x个记录 y for 取数量，取y个记录 等同于 limit y offset x

题解1

SELECT emp_no,salary
FROM salaries
ORDER BY salary DESC
LIMIT 1,1

题解2

SELECT emp_no,salary
FROM salaries
ORDER BY salary DESC
LIMIT 1
offset 1