MYSQL在几分钟内获得两个数据时间之间的差异，并在字段中更新

Question

我有3个文件id，startdate，enddate的表格。现在我添加了一个名为mins的新字段，如图中所示。

我需要查询才能在几分钟内获得startdate和enddate之间的差异，并存储在mysql字段中。

Answer 1

使用MySQL TIMESTAMPDIFF()：

UPDATE YourTable t 
set t.mins =  ABS(TIMESTAMPDIFF(MINUTE,t.startdate,t.enddate)) ;

Answer 2

如果您稍后添加了分钟列，则应使用以下查询更新表。

 INSERT INTO yourTable 
    SELECT 
      inn.id,
      inn.StartDate,
      inn.EndDate,
      TIMESTAMPDIFF(
        MINUTE,
        inn.StartDate,
        inn.EndDate
      ) AS diff 
    FROM
      `yourTable` inn 
      ON DUPLICATE KEY 
      UPDATE 
        id = inn.id,
        `StartDate` = inn.StartDate,
        EndDate = inn.EndDate,
        Mins = TIMESTAMPDIFF(
          MINUTE,
          inn.StartDate,
          inn.EndDate
        ) ;

假设这是表格的初始状态

  id  StartDate            EndDate                Mins  
------  -------------------  -------------------  --------
     1  2016-11-07 12:53:27  2016-11-30 12:53:35         0
     2  2016-11-02 12:53:41  2016-12-07 12:53:45         0
     3  2016-11-16 12:53:52  2017-02-16 12:53:56         0

执行上述查询会转换表格如下：

    id  StartDate            EndDate                Mins  
------  -------------------  -------------------  --------
     1  2016-11-07 12:53:27  2016-11-30 12:53:35     33120
     2  2016-11-02 12:53:41  2016-12-07 12:53:45     50400
     3  2016-11-16 12:53:52  2017-02-16 12:53:56    132480