custom returns for sql functions

[matheus1lva]

I'm trying to create a "computed" root field, where it depends on other features.

create table viewport_info(
	lat float,
	lng float
);


CREATE OR REPLACE FUNCTION public.defaultmapviewport(hasura_session json)
returns table (
	lat float,
	lng float
)
STABLE
AS $function$
  SELECT lat, lng
  FROM places
  WHERE slug_en = (CASE hasura_session ->> 'x-hasura-default-country-code'
    WHEN 'FR' THEN 'city-paris' 
    WHEN 'ES' THEN 'municipality-madrid'
  END);
$function$ language SQL;

Even though the base graphql field is created, when I switch to relay it does not create it. Even though I tried to add a new id field, it didn't work.

How can I make it work?