What software are you using to view the queries?

I use DataGrip. It’s fantastic.

I believe it is a glaring symptom of federation replication failure. Data isn’t making it back from the remote server to confirm the join. Either the outbound never made it to the remote, or the remote never made it back to your server. Multiple instances have had users complaining of these federation failures, example: https://lemmy.ml/post/1280517

You (the end-user) can try to cancel the join of the community and join again to trigger new connection to the server. I would also add the date to the output so you can try to see when these failures are happening (are they all on the same day?)

Yeah sorry, I didn’t realize you meant remote community joins. I have had that problem in fact I still can’t join several communities due to that issue.