IN让我们的代码简洁
WHERE state =’VA’ OR state=’VB’ OR state=’VC’
可以直接写成 WHERE state in (‘VA’,’VB’,’VC’)

BETWEEN让我们的代码简洁 可以比较同一属性的范围数值
WHERE points >=1000 AND points <=2000
->
WHERE points BETWEEN 1000 AND 2000