/**
  * Creates a PDO object and connects to the database.
  *
  * @return void
  * @throws Zend_Db_Adapter_Exception
  */
 protected function _connect()
 {
     if ($this->_connection) {
         return;
     }
     parent::_connect();
     if (isset($this->_config['options']['init_commands']) && is_array($this->_config['options']['init_commands'])) {
         foreach ($this->_config['options']['init_commands'] as $sqlInitCommand) {
             $this->_connection->exec($sqlInitCommand);
         }
     }
 }