Thank you for bringing this up! I hope popular web frameworks start adopting dataclasses for representing their models and use type safe method chaining APIs to interface with business logic.

On Fri, Apr 23, 2021 at 10:18 AM Tin Tvrtković <> wrote:

from dataclasses import fields

user_projection: tuple[str] = await fetch_projection(User, id=1, fields(User)[1])

In fquery [1], this would be spelled as:


My request is to consider that some of the implementations may not be presenting a flat result set. For example this query:

       resp = (
            .project(["name", ":id"])


Without the "to_json()" it produces a graph of similarly nested python objects.

Type checkers that can understand these queries and provide type safety to consumers of the result set would be a great reason for web frameworks to adopt this vs the status quo where the internals of a relational database are exposed via a python API.