CREATE TABLE `news` (
    `id` int(10) unsigned NOT NULL auto_increment,
    `dt` int(10) unsigned NOT NULL,
    `text` text NOT NULL,
    PRIMARY KEY  (`id`),
    KEY `dt` (`dt`)
);

CREATE TABLE `news_order` (
    `num` int(10) unsigned NOT NULL auto_increment,
    `id` int(11) NOT NULL,
    PRIMARY KEY  (`num`),
    KEY `num_id` (`num`,`id`)
);

TRUNCATE `news_order`;
INSERT INTO `news_order` SELECT NULL, `id` FROM `news` ORDER BY `id` DESC;

SELECT `news`.`id`, `news`.`dt`, `news`.`text`
FROM (
    SELECT `id`
    FROM `news_order`
    WHERE `num` > $from AND `num` < $till
    ORDER BY `num`
) AS `no`
INNER JOIN `news` ON `news`.`id` = `no`.`id`

SELECT `id`, `dt`, `text`
FROM `news`
LIMIT $from, $count

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