Need to use Joomla database credentials/objs in a cron job - Joomla! Forum - community, help and support

i'm migrating joomla 1.7 site use joomla 2.5. prior developers did lot of regrettable things, 1 of create nightly cron job ran dozens of queries directly on joomla db using mysql_query.

i'm hoping modify database access in cron job such uses joomla classes , credentials access database rather having separate database connect/query structure unto itself. in particular:
* db credentials in configuration.php
* jdatabase object (and related exceptions or other classes)

is there standardized way this?

please note that:
* not want script live in web root, lest set off accessing script in web browser
* don't expect create component/module/plugin here , hoping avoid additional overhead required these more formalized concepts.
* ideally whatever technique use forward-compatible joomla 3, etc. don't face rewrite when upgrade again.
* don't want modify of joomla code project cannot upgraded -- i.e., don't want alter files break compatibility joomla.

any provide appreciated. want done , looking @ around 60 queries must adapted (and quickly!) -- don't want have fix them again in future.

https://github.com/joomla/joomla-platform-examples/blob/master/cli/database
an example on how work db joomla platform cli