I'm using PostgreSQL 9.6 (can move to 12 if needed).
I have many schemes with same table_name, so I want to pass scheme_name to functions like this:
CREATE FUNCTION public.test()
RETURNS TABLE(base_name text, slow real)
LANGUAGE plpgsql
AS $$
BEGIN
RETURN QUERY
SELECT * FROM scheme_name.bases, scheme_name.servers
WHERE scheme_name.bases.id = scheme_name.servers.id;
END
$$;