Question

我正试图从每天的数据库中获得最低和最高温度。但他以错误的顺序检索日期年份我得到这样的值：

阵列（[00-00-0000] =＆gt; 22 [00-08-2013] =＆gt; 22 [01-08-0201] =＆gt; 24 [01-08-0213] =＆gt; 24 [ 01-08-2013] ......

如果我使用PHPmyAdmin来验证表中的数据，那么似乎没问题。

码

$query = "SELECT  DATE_FORMAT(`Datum`, '%d-%m-%Y') as Datum1, min(`Temperatuur`)as minTemp ,max(`Temperatuur`)as maxTemp FROM `tableGreenhouse`  GROUP BY `Datum1` ORDER BY 1";

$result = $mysqli->query($query) or die($mysqli->error.__LINE__);

if($result->num_rows > 0) {
    while($row = $result->fetch_assoc()) {
        $date = $row['Datum1'];
        $Temp1 = $row['minTemp'];
        $Temp2 = $row['maxTemp'];

        $dataArray1[$date]=$Temp1;
        $dataArray2[$date]=$Temp2;  

    }

}

print_r($dataArray1);
print_r($dataArray2);

Answer 1

您的查询似乎没有任何问题。

也许你可以尝试使用以下代码将变量转换为某种类型：

if ($result->num_rows > 0) {
    // In some cases, code breaks if you do not do this...
    // Experienced it myself a few times.
    $dataArray1 = array();
    $dataArray2 = array();

    while($row = $result->fetch_assoc()) {

        /* For error checking, enable following statement: */
        // var_dump($row);

        $date = (string)$row['Datum1'];
        $Temp1 = (float)$row['minTemp'];
        $Temp2 = (float)$row['maxTemp'];

        $dataArray1[$date]=$Temp1;
        $dataArray2[$date]=$Temp2;
    }
}

Mysql查询显示日期结果有点混淆

1 个答案: