Single object lookup by unique key

It would be useful if we could lookup single objects by their unique fields other than the primary key.

user_by_email(email: "[e-mail]") { id email }

For composed unique fields it could be something along the lines of

order_by_user_id_and_invoice_id(user_id: 1, invoice_id: 1) { id email }

I presume we could automatically get this functionality based on the unique indexes in postgresql. It is a bit nicer than with the where clause when we know there will only be a single item.

[gsnunes]

Would be nice if we had a query_by_uk exactly like query_by_pk but base on the unique keys, this way we don’t need to use the search queries that return an array.

[joanrodriguez]

This would greatly help