CREATE TABLE sub ( id int(10) unsigned NOT NULL AUTO_INCREMENT PRIMARY KEY, msg varchar(200) ) ENGINE=MyISAM DEFAULT CHARSET=utf8; CREATE TABLE mrg ( id int(10) unsigned NOT NULL AUTO_INCREMENT KEY, msg varchar(200) ) ENGINE=MERGE UNION=(sub); こういうマージテーブルを作って、マージテーブルにアクセスすると、 ERROR 1168 (HY000): Unable to open underlying table which is differently defined or of non-MyISAM type or doesn't existこんなエ