From PHPBB用户手册

用于保存用户发表文章过程中保留的草稿内容
CREATE TABLE `phpbb_drafts` (
  `draft_id` mediumint(8) unsigned NOT NULL auto_increment,
  `user_id` mediumint(8) unsigned NOT NULL default '0',  //草稿的所有者, 用户ID
  `topic_id` mediumint(8) unsigned NOT NULL default '0', //草稿回复的主题ID
  `forum_id` mediumint(8) unsigned NOT NULL default '0', //主题所在的版面ID
  `save_time` int(11) unsigned NOT NULL default '0', //保存时间
  `draft_subject` varchar(255) collate utf8_bin NOT NULL default '', //草稿标题
  `draft_message` mediumtext collate utf8_bin NOT NULL, //草稿内容
  PRIMARY KEY  (`draft_id`),
  KEY `save_time` (`save_time`)
) ENGINE=MyISAM DEFAULT CHARSET=utf8 COLLATE=utf8_bin AUTO_INCREMENT=1 ;