Which view is better optimized ?

[Landry Soules]

Hello,

I have a simple users document containing fields such as gender, age and
last seen date.
I have to request these documents by age, or gender, or last seen date or a
mix of these criteria.
My question is : is it more efficient to create a single view containing
several emit, for example:
emit([doc.age, doc.gender, doc.lastSeen], doc);
emit([doc.gender, doc.age, doc.lastSeen], doc);
or to create several views, each of them containing one emit statement ?

Thanks.