$sql = "SELECT date, index FROM table WHERE date='dateVal' AND index<'indexVal' ORDER BY index ASC LIMIT 1"; $result = mysql_query($sql); $row = mysql_fetch_row($result); //这里是正常情况,既有值 if(empty($row)){ //所谓的极端情况来了。。,既上一个有单日期的最后一单 $sql = "SELECT date, index FROM table WHERE date<'dateVal' ORDER BY date,index DESC LIMIT 1"; $result = mysql_query($sql); $row = mysql_fetch_row($result); } print_r($row);