From PHPBB用户手册

# Table: 'phpbb_poll_votes'
CREATE TABLE phpbb_poll_votes (
	topic_id mediumint(8) UNSIGNED DEFAULT '0' NOT NULL,  投票隶属的主题ID
	poll_option_id tinyint(4) DEFAULT '0' NOT NULL, 投票的选项ID
	vote_user_id mediumint(8) UNSIGNED DEFAULT '0' NOT NULL, 投票用户ID
	vote_user_ip varchar(40) DEFAULT '' NOT NULL, 投票用户的ip地址
	KEY topic_id (topic_id),
	KEY vote_user_id (vote_user_id),
	KEY vote_user_ip (vote_user_ip)
) CHARACTER SET `utf8` COLLATE `utf8_bin`;