Question

Point out the correct statement.

(a) To access variables in expressions, use a string that prefixes the variable name with $$$

(b) Expressions can include field paths and system variables, literals, expression objects, and expression operators

(c) To specify a field path, use a string that prefixes with a dollar sign % the field name or the dotted field name

(d) All of the mentioned

The question was posed to me in homework.

I'm obligated to ask this question of Aggregation Mechanics in chapter Aggregation Concepts and Aggregation Mechanics of MongoDB

Answer 1

Correct choice is (b) Expressions can include field paths and system variables, literals, expression objects, and expression operators

Easiest explanation: Expressions can be nested.