Question

我有一个如下所示的数据集

----------------------------------------------------
| NodeID            | Status  | Time               |
----------------------------------------------------
|  101              | Up      |2016-04-27 10:00:35 |
----------------------------------------------------
|  101              | Down    |2016-04-27 10:43:12 |
----------------------------------------------------
|  101              | Up      |2016-04-27 11:05:48 |
----------------------------------------------------
|  156              | Up      |2016-04-27 08:17:10 |
----------------------------------------------------
|  156              | Up      |2016-04-27 08:56:30 |
----------------------------------------------------
|  156              | Down    |2016-04-27 09:06:12 |
----------------------------------------------------

我正在尝试获取可用性（每个应用程序启动时的时间％）。该表不能具有自动增量字段，因为将使用预定作业连续删除记录。

我尝试使用行号和自联接来获取每行的下一条记录的时差：

SELECT A.NodeId, A.Status, TIMESTAMPDIFF(MINUTE,A.time,B.time) AS timedifference 
FROM (

SELECT @row_number:=@row_number+1 AS row_number,nodeId, status, time FROM sw_node_status,
(SELECT @row_number:=0) AS t) as A 

INNER JOIN 
(
SELECT @row_number:=@row_number+1 AS row_number,nodeId, status, time FROM sw_node_status,
(SELECT @row_number:=0) AS t
) as B ON B.row_number = (A.row_number + 1 )
ORDER BY A.NodeId ASC

但是需要很长时间才能运行并且只给我一条记录。预期的输出为：

| NodeID            | Status  | Time               | Duration (mins
----------------------------------------------------------------
|  101              | Up      |2016-04-27 10:00:35 | 43 
----------------------------------------------------------------
|  101              | Down    |2016-04-27 10:43:12 | 23
----------------------------------------------------------------
|  101              | Up      |2016-04-27 11:05:48 | 0
----------------------------------------------------------------
|  156              | Up      |2016-04-27 08:17:10 | 39
----------------------------------------------------------------
|  156              | Up      |2016-04-27 08:56:30 | 10
----------------------------------------------------------------
|  156              | Down    |2016-04-27 09:06:12 | 0
----------------------------------------------------------------

Answer 1

SELECT @prev_time:=time,
       nodeId, status, time,
       TIMESTAMPDIFF(MINUTE,A.time,@prev_time) AS timedifference 
FROM sw_node_status, (SELECT @prev_time:=some_initial_time) as init

MySQL +基于状态的持续时间

1 个答案: