For the $all array operator, the quiz says:
The sections field in this collection identifies supplementary readings available in a given document by a three-character code. How many documents list: “AG1”, “MD1”, and “OA1” among the codes in their sections array.
I have a local installation and looked at the schema - there is no “sections” field. Do I have an out-of-date collection?
EDIT: Yes, I just connected to the online M001 cluster and the “sections” field is there. I can complete this exam question now, since I can connect via port 27017 again, but I’m curious why the local and online data are out of sync.