TypeError: Cannot read property 'length' of undefined

[chenhb-zte]

it crashed, report the issue "TypeError: Cannot read property 'length' of undefined".
querys were working, switched to 'Bar gauge' panel, it could work normally.

Please help me, thanks

[nicklasjepsen]

I am also getting this error/crash of the Grafana UI when using the Pie Chart.

[SIM0N-F]

Hello, I have this issue too, I use Grafana 7.3.1 and pie chart 1.6.1.
This breack my Grafana UI

[AlexanderGPY]

i got same problem，This problem occurs when I add the second element to the pie chart and I can guarantee that my query is correct
env: grafana 7.3.1

[tewe]

Duplicate of #217

[ketul-kothari]

My team is also facing the same problem. Interestingly, the charts are working with older version of grafana (< 7.0.5). Any version greater than this and they start breaking.

[svkempf]

Also same issue here :-(
Grafana Version is 7.3.7

All fine in table view. After switching to Pie Chart the "Cannot read property 'length' " error comes up.

Upgrading to Grafana 7.4.3 changed the issue: Now no more error message but panel stays black.

My issue might also be related to this one as I'm using Azure Data Explorer: grafana/azure-data-explorer-datasource#30