Mysql query problems (total amount of time) - mysql

Question

I’m stuck..
I have the indicators on my heater connected to a raspberry pi. The pi then put the changed state (on and off) with the time into a mysql database.
Before I’ve used PHP to present the data but I’m now trying out Grafana. And I cant get the mysql query to present what I want.
I need to know how much time the heater has been activated (0/1) in the specified time range (typically the last 24h). And I need to take into account that the time range may start with ”0”, meaning that the heater has been on the time before that. And the same if it ends with ”1”.
And maybe also the percent of the day where it’s been activated.
Can someone please help me?
I'm looking for a result like this
+-------+--------------+--------------+
| value | secondsOfDay | PercentOfDay |
+-------+--------------+--------------+
| 0 | 28800 | 33.3 |
| 1 | 57600 | 66.6 |
+-------+--------------+--------------+
I've prepared:
http://sqlfiddle.com/#!9/556364a
Thanks!

Answer 1

To get the required data, you can use the following query:
NOTE: Depending on CURRDATE() the examples will fail. You can ofc. replace CURDATE() with a fixed value like 2018-11-27;
Explanation:
The query is joining the table with itself, taking into account, that on/off follows each other (L.id = R.id -1)
The query is selecting Any result, where "on" or "off" is today.
IF on was yesterday, the on-time is "corrected" to 00:00:00 of today: case when L.Time < CURDATE() then CURDATE() else L.Time end as onTime
IF the last entry is on, the off-time is "corrected" to 00:00:00 of tomorrow: COALESCE(R.time, CURDATE() + Interval 1 day) (note: You maybe want to use NOW() instead of CURDATE() + Interval 1 day, to have the current amount of seconds until "now")
The Same two methods are used to calculate the running seconds.
Query:
SELECT
L.playtime_id AS LID,
R.playtime_id AS RID,
case when L.Time < CURDATE() then CURDATE() else L.Time end as onTime,
COALESCE(R.time, CURDATE() + Interval 1 day) AS offTime,
(
UNIX_TIMESTAMP(COALESCE(R.time, CURDATE() + Interval 1 day)) -
UNIX_TIMESTAMP(case when L.Time < CURDATE() then CURDATE() else L.Time end)
) as RunningSeconds
FROM item0005 as L
LEFT JOIN item0005 AS R
ON L.playtime_id = R.playtime_id -1
WHERE
L.`value` = 1 AND
(
DATE(L.Time) = CURDATE() OR
DATE (R.Time) = CURDATE()
)
;
Result Example:
LID RID onTime offTime RunningSeconds
2 3 2018-11-27T09:00:00Z 2018-11-27T11:26:24Z 8784
4 5 2018-11-27T11:26:27Z 2018-11-27T11:28:29Z 122
6 7 2018-11-27T11:29:39Z 2018-11-27T11:39:55Z 616
8 (null) 2018-11-27T11:50:55Z 2018-11-28T00:00:00Z 43745
Example assuming 00:00:00 of tomorrow: http://sqlfiddle.com/#!9/20bc14/1
Example using NOW() to count up seconds if the last state is on: http://sqlfiddle.com/#!9/3c6227/1
If you just need the Aggregations out of this, you can use another Surrounding Select and calculate the Percentage by knowing a day has 86400 seconds:
SELECT
SUM(RunningSeconds) AS RunningSeconds,
SUM(RunningSeconds) / 86400 * 100 AS PercentageRunning
FROM (
...
) as temp;
http://sqlfiddle.com/#!9/20bc14/5

Answer 2

try this
SELECT VALUE, SUM(TIME_TO_SEC(TIMEDIFF(T2,T1))), 100*SUM(TIME_TO_SEC(TIMEDIFF(T2,T1)))/86400 FROM
(SELECT A.VALUE AS VALUE, COALESCE(B.TIME, TIMESTAMP(CURDATE()-2)) AS T1, A.TIME AS T2
FROM ITEM0005 A
LEFT JOIN ITEM0005 B
ON A.PLAYTIME_ID-1= B.PLAYTIME_ID
WHERE A.VALUE='0'
UNION
SELECT '1' AS VALUE, A.TIME AS T1, COALESCE(B.TIME, TIMESTAMP(CURDATE()-1)) AS T2
FROM ITEM0005 A
LEFT JOIN ITEM0005 B
ON A.PLAYTIME_ID= B.PLAYTIME_ID-1
WHERE A.VALUE='0') C
GROUP BY VALUE;