Maybe it was just whitespace in the cat# field.
I can't reproduce this. Can you give some more information about how entered the edit?
It shouldn't be possible to have a catalogue number that's only whitespace now, so that shouldn't be the reason.
What I know is that the release had a bullet point in the sidebar under "Label", that's what made me suspicious in the first place. The editing history tells me that in http://musicbrainz.org/edit/19361332 I did not remove the label but simply blanked the field which perhaps didn't do the job the way I had expected it to. Only in http://musicbrainz.org/edit/19885525 I clicked on the red cross to remove it.
Has happened again, see http://musicbrainz.org/release/edb1380b-90d3-428a-9dc5-b095768c990a/edits and yes, it's because I once again blanked the label field instead of removing the label entry.
I think you might be removing something that is in this:
select count(*) from release_label where label is null and catalog_number is null;
@HumHumXX: "and yes, it's because I once again blanked the label field instead of removing the label entry" - could you clarify this in a bunch of steps I can use to reproduce entering these failed rows? We will have a constraint soon that will prevent this from happening soon, but I think it might still be possible to submit a form that will cause an exception.
Which server can I use for this? Test isn't working as I don't seem to have auto-editor privileges there. On the main server, removing or editing a label is an auto-edit, on test it's not.
You can give yourself auto-editor privileges on test - just go to your profile and click Edit User. Of course, since test is insanely slow, that might still be a pain to check while getting timeouts - other option is probably to try in one of our sandboxes, where you can also edit your privileges. Try http://reosarevok.mbsandbox.org/
Thanks, I did it on test, it's very responsive, actually.
1. Go to any release, e.g. http://test.musicbrainz.org/release/cedcb155-d95d-4630-ab27-e5518ebd3f2b
3. Blank the label field (+ the cat#, if available)
4. "Edit Note"
5. "Enter edit"
7. Press "X" to remove the label
8. "Edit Note"
9. "Enter edit"
That's it. Tested with Opera 12.12 and Firefox 18 on Debian Wheezy.
As you can see, I left the release in a state where there's only a bullet point but no label. I can re-add a label, then blank the field again and then remove the label that isn't there again. It always shows the same behaviour.
In review at https://github.com/metabrainz/musicbrainz-server/pull/44