UPDATE mdl_course SET modinfo = ?,sectioncache = ? WHERE id=?
Behavior this time unlike last time: user could log into Moodle but their MyMoodle page displayed "error writing to database".
developer mode error reporting showed what I attached. (very very long) last time same user could see mymoodle but just one course was not accessible showing the same error.
I created a 2nd username for her and as I was adding that user to each of her courses one course only failed to even let me click it as me the admin throwing the same error above. After deleting that course, her original login worked immediately (and 2nd one of course too).
Suspected cause: Elluminate ghost left over not sure how this time as I can't enter the course.
I hope this helps someone.