Set field value as query label / alias for a PostgreSQL data source

Hi, I’m trying desperately to properly configure a panel using PostgreSQL as a data source. This panel has two queries from the same table with different conditions. Data is visualized via a time series.

The example output data looks like this:

date value meter
2023-11-12 10:11:12 0.444 Meter 1
2023-11-11 10:11:12 0.333 Meter 1
2023-11-10 10:11:12 0.222 Meter 1
2023-11-09 10:11:12 0.111 Meter 1

and similar for the second query:

date value meter
2023-11-12 10:11:12 3 Meter 2
2023-11-11 10:11:12 2.5 Meter 2
2023-11-10 10:11:12 2.0 Meter 2
2023-11-09 10:11:12 1.5 Meter 2

The problem: the chart shows the two graphs, but both have value as the label. Unfortunately, the PostgreSQL provides no option to set a label directly on the query.

  • What Grafana version and what operating system are you using?

    • Grafana in Docker, v10.1.1 (0cfa76b22d)
  • What are you trying to achieve?

    • I would like to set the label of a query from a field, in this case it would be the value of meter.
  • How are you trying to achieve it?

    • I have no idea. I tried so many things I found on the internet, but none worked. Neither using data links in the Display Name config, nor using transforms to change the outputs. Closest I could get is with the Config from field transform, but it removes all but one query results.

Related but without working answer:

What kind of visualization?

Also what are the two where conditions?

It’s a time series, conditions select individual meters in my case.

so instead of using the column name meter, what if you tried to use

select date as time,	
       meter as metric
  from table
 order by 1

and make sure Format is time series


bottom query is just me mocking your data

Thank you very much! Using metric as the name for the field worked.
May I ask how you know that it is supposed to be like that? I don’t know where in the documentation this could be found.

1 Like

sorry I don’t remember where in the doc that is