Problem Statement/Rationale

When I connect to Atlas Data Lake (both locally and in our dev environment) and issue the following command:

db.coll.find({a: 1}).explain()

It generates an explain command with a verbosity level of: "allPlansExecution". This is the BSON doc we get for the command:

{"explain": {"find": "coll","filter": {"a": {"$numberInt":"1"}}},"verbosity": "allPlansExecution","lsid": {"id": {"$binary":{"base64":"ed4DRneUSC2vxB5Kd+CwSw==","subType":"04"}}},"$db": "test"}

This is problematic for Data Lake, because we do not support allPlansExecution.

According to the docs: https://docs.mongodb.com/manual/reference/method/cursor.explain/ the default verbosity level should be "queryPlanner"

Steps to Reproduce

See above. Note: I was not able to repro this on the server. Mongosh seemed to be using the correct verbosity level when running against the server.

Expected Results

Mongosh should use the "queryPlanner" verbosity level by default when connected to ADL instance if necessary.

Actual Results

Mongosh is sending a command doc with the verbosity level: allPlansExecution

Additional Notes

I asked about this in #mongosh: https://mongodb.slack.com/archives/CUHC9R8J0/p1641342447132900

and was told to a file a ticket. I'm happy to help an engineer from the mongosh connect to an ADL if necessary.