I'm not sure I'm understanding how to use Drupal with multiple database connections. I know I can setup more than one connection. It's not that.
I use SQL. I do not want to not use SQL for this part of Drupal (it is not part of the core of Drupal). It is a "report" almost, except it can link to other data in other databases. I have to query three-plus databases and bring back the data and have it display in the CMS like any other set of data someone might want.
For example, I do not wish to do this or this (from Drupal's documentation):
$result = db_select('example', 'e') ->fields('e', array('id', 'title', 'created')) ->condition('e.uid', $uid) ->orderBy('e.created', 'DESC') ->range(0, 10) ->execute();
The queries are large and complicated. Am I fighting against the CMS/Framework, if I use
[db_query]() everywhere for these outside databases that are unrelated to Drupal's core?
I can't find examples of anyone doing this, but I am still searching.