使用sql计算之前的时间

假设我有下表test它有列id, time, post这是它拥有的数据的样本。

-----------------------------------
   id           time        post
-----------------------------------     
    1   2018-06-17 16:12:30 post1
    2   2018-06-17 16:13:09 post2
    3   2017-06-15 16:12:30 post7
----------------------------------

我想仅使用打印出来SQL自每个帖子添加到数据库以来多少天、小时、分钟和秒前

好的，这是我的第一次尝试

SELECT
    id,
    time,
    NOW(),
    CONCAT (
    FLOOR(TIME_FORMAT(SEC_TO_TIME(NOW() - `time`), '%H') / 24),
    ' Days ',
    MOD (TIME_FORMAT(SEC_TO_TIME(NOW() - `time`), '%H'), 24),
    ' Hours ',
    TIME_FORMAT(SEC_TO_TIME(NOW() - `time`), '%i Minutes %s Seconds'),
    ' ago' 
    ) AS `ago` 
FROM
    `test`;

但它似乎没有给出正确的计算，例如上面示例的输出是

1   2018-06-17 16:12:30 2018-06-17 20:38:08 0 Days 11 Hours 49 Minutes 38 Seconds ago
2   2018-06-17 16:13:09 2018-06-17 20:38:08 0 Days 11 Hours 48 Minutes 19 Seconds ago
3   2017-06-15 16:12:30 2018-06-17 20:38:08 34 Days 22 Hours 59 Minutes 59 Seconds ago

如你所见，在id = 3然而差异应该不仅仅是34打印出来的天数

那么代码有什么问题吗？ 〜谢谢你

你可以尝试这个查询。计算间隔TIMESTAMPDIFF and TIMESTAMPADD功能。

SELECT
    id,
    time,
    NOW(),
    CONCAT (
    TIMESTAMPDIFF(DAY,`time`, NOW()),' Days ',
    TIMESTAMPDIFF(HOUR, TIMESTAMPADD(DAY, TIMESTAMPDIFF(DAY, `time`, NOW()), `time`), NOW()),' Hours ',
    TIMESTAMPDIFF(MINUTE, TIMESTAMPADD(HOUR, TIMESTAMPDIFF(HOUR, `time`, NOW()), `time`), NOW()), ' Minutes ',
    TIMESTAMPDIFF(SECOND, TIMESTAMPADD(MINUTE, TIMESTAMPDIFF(MINUTE, `time`, NOW()), `time`), NOW()), ' Seconds '
    ' ago' ) AS `ago` 
FROM
    `test`;

sqlfiddle:http://sqlfiddle.com/#!9/5e8085/2

NOTE

例如，您想要获取间隔SECOND

让我们一步步来了解一下：

1.TIMESTAMPDIFF(MINUTE, time, NOW())获取间隔MINUTE之间time and NOW()

2.TIMESTAMPADD(MINUTE, TIMESTAMPDIFF(MINUTE, time, NOW()), time)追加间隔MINUTE to time，让他们只有间隔时间second.

3.计算秒间隔。