SELECT (Photo {uri}, User {name, email})
FILTER Photo.author.id = User.id;
The tutorial database uses links, and so instead of having an author_id we have author.id, but having an author_id property would work just fine---except that then you'd have to do all the joins manually.
table1: id, name
table2: table1_id, level
Desired result:
{id, name, level}