From PHPBB用户手册

# Table: 'phpbb_acl_users' 用户的权限信息
CREATE TABLE phpbb_acl_users (
	user_id mediumint(8) UNSIGNED DEFAULT '0' NOT NULL, 对应的用户ID
	forum_id mediumint(8) UNSIGNED DEFAULT '0' NOT NULL, 对应的版面ID
	auth_option_id mediumint(8) UNSIGNED DEFAULT '0' NOT NULL, 对应的权限选项ID
	auth_role_id mediumint(8) UNSIGNED DEFAULT '0' NOT NULL, 权限角色ID
	auth_setting tinyint(2) DEFAULT '0' NOT NULL, 权限的设置值，可以是0, 1, -1, 分别对应ACL_NEVER, ACL_YES, ACL_NO
	KEY user_id (user_id),
	KEY auth_option_id (auth_option_id),
	KEY auth_role_id (auth_role_id)
) CHARACTER SET `utf8` COLLATE `utf8_bin`;