getMaxMin

public function getMaxMin($nodeId, $datetimestart, $datetimeend) {

        $values = array(
            ':nodeId'        => $nodeId,
            ':datetimestart' => $datetimestart,
            ':datetimeend'   => $datetimeend
        );

        $sqlmax = "SELECT
            MAX(temperature) as temperature,
            MAX(humidity) as humidity,
            MAX(pressure) as pressure,
            datetime
            FROM measurement
            WHERE nodeId =:nodeId
            AND datetime BETWEEN :datetimestart
            AND :datetimeend";

        $sqlmin = "SELECT
            MIN(temperature) as temperature, datetime as tdate,
            MIN(humidity) as humidity, datetime as hdate,
            MIN(pressure) as pressure, datetime as pdate
            FROM measurement
            WHERE nodeId =:nodeId
            AND datetime BETWEEN :datetimestart
            AND :datetimeend";

        $max = $this->queryDatabase($sqlmax, $values);
        $min = $this->queryDatabase($sqlmin, $values);
        $data = array(
            'max' => $max[0],
            'min' => $min[0]
        );
        //print_r($min);
        return $data;
    }