两种写法。如图，4种重合情况和2种不重合情况。
-- 时间段 a,b SELECT * FROM table WHERE (start_time >= a and end_time <= b) -- 被包含了 or (end_time >= a and end_time <=b) or (start_time >= a and start_time <=b) or (start_time <= a and end_time >=b)
解析：where后的4个条件分别代表了图中4种重合的情况。
但是第一种情况被2和3包含了，所以简化一下写法：
SELECT * FROM table WHERE (end_time >= a and end_time <=b) or (start_time >= a and start_time <=b) or (start_time <= a and end_time >=b);
第二种写法：
SELECT * FROM table WHERE not (start_time > b or end_time < a);
原文：https://www.cnblogs.com/chenyablog/p/14644706.html