We noticed there was a performance issue while browsing the SDG
Management section and when one of our tests started failing sometimes
because the request to the relations#index controller took too long.
The issue proved to be `SDG::Target#<=>`. This method calls `.goal` for
each target, meaning we were generating 169 database queries when
sorting all targets.
So we're comparing codes directly to minimize the number of database
queries and improve performance. Requests to the relations index take
now less than third of the time they used to take.
This is similar to what we do with investments, which belong to a heading
but also belong to a budget. In our case, the reason is we've been asked
to add local targets which belong to a goal but are not related to any
existing target.
Even though we're not implementing that case right now, we're adding the
relation so we don't have to add data migrations in the future.
This way translators will find a hint indicating they must use two lines
and not three or more, since the title is optimized for being displayed
in two lines.
The same it's done in the UN official SDG pages.
We could try to split the string on a space which is more or less in the
middle. However, this wouldn't work on languages which don't have spaces
between works, like Chinese.
So in the end I've added a new translation key, where the title is
supposed to be split in several lines the same way it's done by the UN.
and its relation with the SDG goal model.
Add comparable module be able to sort collections of targets
by code attribute.
Co-Authored-By: Javi Martín <35156+javierm@users.noreply.github.com>
Similar to what we do with settings, only for settings we return the
value of the setting (which is what we're going to need most of the
time), and here we return the object.
Since data for this model (title and description) is not generated in
CONSUL but by the United Nations, we aren't storing it in the database
but in our YAML translation files.
The reasoning is as follows. Suppose that, a few months after CONSUL
gets SDG support, a new language is added to CONSUL.
With YAML files, getting the texts in the new language would mean
updating CONSUL to include the new language.
But if we store these texts in the database, it means we have to update
the databases of all existing CONSUL installations, either each
installation by themselves (duplicating efforts) or running a rake task
(which we would have to write each time).
So we believe using translations works better in this case.
We're still storing records in the database with the code, so they can
be easily referenced via `has_many` or `has_many :through` associations.
