I am afraid I do not know how exactly to reproduce this - but I know for sure this course was created on 2.8 and without any fancy hacks. An error was experienced by Helen when bulk-deleting courses on learn.moodle.net and then once I had worked out which course was affected - I could reproduce the error by visiting the gradebook of the course in question:
"Found more than one record in fetch() !"
Unfortunately that error message provides absolutely no details... But once I hacked the code I found the problematic record.
The timestamp suggests double click or something??
Anyway what do:
- The gradebook code could at least provide some details in DEBUG_DEVELOPER mode?
- Maybe there needs to be some double click prevention in the category creation code?
- Maybe the gradebook should be more fault tolerant when deting records?