Hm, I see now where we're talking past each other - I was thinking more along the lines of "user has orders has order lines has products has prices" (where you

Hm, I see now where we're talking past each other - I was thinking more along the lines of "user has orders has order lines has products has prices" (where you might traditionally make a (hierarchy of) database view(s)). Not "user has orders", and also "user has favorite products".