if not found then
		insert into tag (tag) values (usort(my_tag));
		select id_tag from tag where usort(my_tag) = tag into tag_id;
	end if;
	return tag_id;
end;
$$;

-- this function returns id of site array
create or replace function get_site(my_site text[]) returns integer
	language plpgsql strict
	as $$
declare
	site_id integer;
begin
	select id_site from site where my_site = site into site_id;
	if not found then
		insert into site (site) values (my_site);
		select id_site from site where my_site = site into site_id;
	end if;
	return site_id;
end;
$$;

-- transforms domain into ordered array for indexing
CREATE FUNCTION tripdomain(url text) RETURNS text[]
	LANGUAGE plpgsql IMMUTABLE STRICT
	AS $_$
declare
	result text[];