I found something myself, my previous attemp was almost correct:
SELECT
UNIX_TIMESTAMP(DATE_FORMAT(time,“%Y-%m-%d %H:%i:%s”)) as time_sec,
value
FROM
xiaomi_th_alex_temperature_0026
I’m only missing how I can give the series a name, now all of them are called ‘unknown’:
That’s the label for the graph/table it selves, not for the series.
With InfluxDB as a datasource you have this option:
I only use the Table Panel for MariaDB data, so I can’t say if it has that option as well.
What happens if you define it in your SQL statement? Something like:
SELECT
UNIX_TIMESTAMP(DATE_FORMAT(time,"%Y-%m-%d %H:%i:%s")) as time_sec,
value as myvaluename
FROM
xiaomi_th_alex_temperature_0026
I had the same problem.
The first google search result pointed out the solution:
The workaround is to use the FLOOR function, e.g.
FLOOR(UNIX_TIMESTAMP(time)) as time_sec
Thx, this is working fine!
Do you also have a solution to display correct series labels?
Sure thing:
SELECT
FLOOR(UNIX_TIMESTAMP(time)) as time_sec,
value,
'Your custom metric name' as metric
FROM your_sql_column_name
WHERE $__timeFilter(time)
ORDER BY time ASC;thanks!
Now I can do everything with my Mariadb, no need for influxdb 
Guys
thanks a lot for sharing your solutions - I was already giving up with Grafana but after finding this thread its working - finally
Can anyone of you tell me how to adjust this script when I want to display more than one line in a chart?
Thanks & regards
John
I simply added a second query, or a third, fourth…
Sorry to re-live this topic.
I’ve spent a little time researching this to no avail…
Using openhab2 on Raspberry pi 3, (openhabian), JDBC Persistance MYSQL, MariaDB, Grafana Graphing… I don’t understand where I can change the following from “value” to the desired name (ie GarageTemp, Greenhouse Temp, etc)
Hopefully this is a quick reply without consuming too many cycles from anyone’s busy day 
AND… I really wish I understood how openhab creates the tablenames in its DB… 
Michael Krug shows the syntax for this but I’m not sure if this goes in Grafana or PHPMyAdmin that I’m using 
AND how to use the proper syntax for my specific application
Thanks Guys!!
You have to change the Alias:
This should be the same name as the item name (you can setup an alias in the *.persist file)
Sounds easy enough… thanks.
I’ll have to look up how to “syntax” the .persist file.
Thanks again… this has been bugging me for a few months now… didn’t have the time to pursue.
No joy…
I do not see the option “Alias” in my Grafana instance. What am I missing?
Well this has been a waste of 2 hours trying to figure out WHY I don’t have the “Alias” option in my Metrics. 
v 5.1.4
It’s enough to start looking for another graphing solution
See some post above, I had the same issue:
