mongo dot notation ambiguity

Question

I love MongoDB, and a certain little ambiguity occurred to me and I was wondering if anyone had seen this before and possibly would know the answer :-).

in mongo, to

Answer 1

A key such as "address.state" isn't legal. From here:

Field names cannot contain dots (i.e. .) or null characters, and they must not start with a dollar sign (i.e. $).