WikiaModel is an abstract class that extends Nirvana/WikiaObject with additional database helper functions. Most Helper classes should extend this class. public function getDB( $db_type = DB_SLAVE ) {return wfGetDB( $db_type ); } public function getWikiDB( $db_type = DB_SLAVE, $db_name = false ) {return wfGetDB( $db_type, array(), $db_name ); } public function getSharedDB( $db_type = DB_SLAVE ) {return wfGetDB( $db_type, array(), $this->wg->ExternalSharedDB ); } public function getDatawareDB( $db_type = DB_SLAVE ) {return wfGetDB( $db_type, array(), $this->wg->ExternalDatawareDB ); } }