/**
* Returns a DbModel with the database connection
* defined in constants.php.
* You can supply a base URI. If a model with the given base
* URI exists in the DbStore, it'll be opened.
* If not, a new model will be created.
*
* @param string $baseURI
* @return object DbModel
* @access public
*/
function &getDefaultDbModel($baseURI = null)
{
$dbStore = ModelFactory::getDbStore();
return ModelFactory::getDbModel($dbStore, $baseURI);
}