Ошибка

SQL запрос:

CREATE TABLE IF NOT EXISTS `wp_commentmeta` (
  `meta_id` bigint(20) unsigned NOT NULL AUTO_INCREMENT,
  `comment_id` bigint(20) unsigned NOT NULL DEFAULT '0',
  `meta_key` varchar(255) COLLATE utf8mb4_unicode_520_ci DEFAULT NULL,
  `meta_value` longtext COLLATE utf8mb4_unicode_520_ci,
  PRIMARY KEY (`meta_id`),
  KEY `comment_id` (`comment_id`),
  KEY `meta_key` (`meta_key`(191))
) ENGINE=MyISAM  DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_520_ci AUTO_INCREMENT=4917

Ответ MySQL:

#1273 - Unknown collation: 'utf8mb4_unicode_520_ci'