Za današnji dan (može i bilo koji drugi samo unesi datum u formatu '2011-09-02')...
PHP kôd:
SELECT HOUR(FROM_UNIXTIME(uts, '%H:%i')) h, MIN(value), MAX(value)
FROM dpt
WHERE
FROM_UNIXTIME(uts, '%Y-%m-%d') = DATE(NOW())
GROUP BY h;
Za 24h...
PHP kôd:
SELECT HOUR(FROM_UNIXTIME(uts, '%H:%i')) h, MIN(value), MAX(value)
FROM dpt
WHERE
UNIX_TIMESTAMP() - 24 * 3600 < uts
GROUP BY h