Laravel Postgres计算时差并得到最小/最大

Question

嗨，我的表结构是这样的，我使用laravel和postgres数据库

id | serving_start_time      | serving_end_time    
1  | 2016-10-05 00:24:08.894 | 2016-10-05 00:24:19.003    
2  | 2016-10-05 00:24:59.875 | 2016-10-05 00:25:13.728    
3  | 2016-10-05 11:43:52.055 | 2016-10-05 11:45:41.561

我想计算'total_serving_time'(serving_start_time-serving_end_time)，只得到最小和最大'total_serving_time'。这在一个查询中可能吗?请帮助

Answer 1

在像下面这样的查询中?

SELECT 
    MIN(serving_end_time - serving_start_time) AS min_total_serving_time,
    MAX(serving_end_time - serving_start_time) AS max_total_serving_time
FROM table;