Checks whether a Flake carries an existence-implying filter constraint.
Such a constraint marks the retrieval path as required rather than optional. Existence is implied by a filtering
constraint whose membership options name at least one non-null value (see hasValueOptions). A null-only
membership set, the ranking and pagination slots, and any constraint behind an aggregate pipe (which filters groups,
not the path) all leave the path optional. A constraint on any descendant marks the whole path to it required.
Checks whether a Flake carries an existence-implying filter constraint.
Such a constraint marks the retrieval path as required rather than optional. Existence is implied by a filtering constraint whose membership options name at least one non-null value (see hasValueOptions). A null-only membership set, the ranking and pagination slots, and any constraint behind an aggregate pipe (which filters groups, not the path) all leave the path optional. A constraint on any descendant marks the whole path to it required.