The non-techie version is that PDO allows you to use a unified way to access a variety of different databases (abstraction) in an object oriented way, but still giving you the option to execute optimzied native Database tools. The reason we’re using it in 097 and beyond is that we’ll eventually roll out versions of MODx that happily run on other databases such as MS-SQL or Postgres. PDO is a very good thing ... sorta like AdoDB, but a lot more robust and a much more modern take on the issue.
PDO (from Zend itself) and our own PHP 4-compatible (or if you don’t have the right drivers installed it _should_ still work) implementation/fallback form what’s the data access part of MODx via
another opensource project. xPDO contains a lot of really cool capabilities for the super-geek-elites to reverse engineer databases and create APIs to access that data to incorporate into their projects. For instance and for reference, we’ve created API for internal use and testing to use the data stored in osCommerce (building our own catalog presentation), Mambo and a custom event tracking application.
The current 097 install from SVN
will be completely blank, free of resources and add-ons. You’ll have to add them in yourself manually for now. You should get a blank page on the front end and you should get nothing in the trees in the Manager (context).
Come to think of it, I wonder if an empty site should at least display a "No website configured..." message?