class Application_Model_DbTable_Base extends Zend_Db_Table_Abstract {

    public function __construct($config = array())
    {
        parent::__construct($config);

        if (Zend_Db_Table_Abstract::getDefaultMetadataCache() === null)
        {
            $frontendOptions = array('automatic_serialization' => true);

            $zendCacheDir = PUBLIC_PATH.'/cache/'; // directory for caching

            if (!file_exists($zendCacheDir))
            {
                mkdir($zendCacheDir, 0777);
            }

            $backendOptions  = array('cache_dir' => $zendCacheDir);

            $cache = Zend_Cache::factory('Core', 'File', $frontendOptions, $backendOptions);
            //$cache->clean(Zend_Cache::CLEANING_MODE_ALL);
            Zend_Db_Table_Abstract::setDefaultMetadataCache($cache);
        }
    }
}