Select returned fields

[MarcelHekkert]

It might be helpful to be able to query->select(fields) to be returned to prevent overhead.

[jamesmoss]

This would be an unnecessary performance optimisation for Flywheel. It's not the same as a traditional database and not intended to be used for millions or even hundreds of thousands of documents. The bottleneck will be the disk reads for each document, not the number or size of the fields returned.