General developer forum

Thanks for reply..
Actually we have run some cli admin commands like,

Fix orphaned question categories
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admin/cli/fix_orphaned_question_categories.php --fix

Fix course/module sequences
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php admin/cli/fix_course_sequence.php -c=* --fix

After this we are running cron.

Does the above command like can create a problem which justify your statement "The issue suggests to me a Quiz or Quiz attempt record that does not relate back to a course module."

Thanks for tips on backup, we are using git checkout -- * to undo changes.