Krinkle has filed a feature request in Phabricator about adding information for the centralauth database to the meta_p.wiki table https://phabricator.wikimedia.org/T186675.
There are pros and cons to doing this, so I thought it would be good to reach out to y'all to see if the pro of making it easier to figure out which database section (e.g. s7) the database lives in outweigh the con of introducing a "family" that identifies non-wiki databases in the "wiki" table.
Please do read and comment on the Phabricator task if you have opinions and would be impacted by the change.
Bryan