"Could not find query part column"

I’m running Grafana v5.4.0 and InfluxDB v1.7.1 on an Ubuntu 14.04.5 LTS server.

I used the following configuration:

After clicking “Save & Test” it shows “Data source is working”.
However when I want to edit the graph panel I can’t select anything and Grafana shows this piece of code in the Metrics tab:
{{ctrl.target.refId}} ({{ctrl.target.datasource}})

On the dashboard and in the Google Chrome console the following error is shown:
“Could not find query part column”

Am I doing something wrong?

Thanks in advance,

The problem was caused by using both Influx and MySQL as data sources in the same dashboard. Using Influx in a new dasboard “solved” the problem. The bug is known to the Grafana developers: https://github.com/grafana/grafana/issues/14394#event-2015698693