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Php 获取最大值的日期和时间_Php_Mysql - Fatal编程技术网

Php 获取最大值的日期和时间

Php 获取最大值的日期和时间,php,mysql,Php,Mysql,我有一个天气读数数据库,我在其中存储所有数据,以便通过显示最大和最小压力的网页使用 问题是我喜欢显示记录这些值的时间和日期 $sql = "SELECT out_pressure, Datetime FROM $table ORDER BY out_pressure DESC LIMIT 1"; $result = mysql_query($sql); $row = mysql_fetch_assoc($result); $max_out_pres

我有一个天气读数数据库,我在其中存储所有数据,以便通过显示最大和最小压力的网页使用

问题是我喜欢显示记录这些值的时间和日期

$sql = "SELECT out_pressure, Datetime
        FROM $table
        ORDER BY out_pressure DESC
        LIMIT 1";
$result = mysql_query($sql);
$row = mysql_fetch_assoc($result);
$max_out_pressure = $row['out_pressure'];
$max_date = $row['Datetime'];
我用于读取最大压力的代码:

$max_out_pressure = mysql_query("SELECT MAX(out_pressure) AS out_pressure FROM $table");
$max_out_pressure = mysql_result($max_out_pressure,0,"out_pressure");
$max_out_pressure = substr($max_out_pressure, 0, 6);
echo "$max_out_pressure";
echo "mbar";
我有列ID,日期时间,压力,温度 表名为READERS

网页:


以前从未制作过数据库或网页,所以我正在努力解决这个问题。

这将获得最大压力和记录日期

$sql = "SELECT out_pressure, Datetime
        FROM $table
        ORDER BY out_pressure DESC
        LIMIT 1";
$result = mysql_query($sql);
$row = mysql_fetch_assoc($result);
$max_out_pressure = $row['out_pressure'];
$max_date = $row['Datetime'];

$Max_date=mysql_querySELECT out_pressure,日期从$table ORDER BY out_pressure DESC LIMIT 1;echo$Max_日期;我写道:$Max_date=mysql_querySELECT out_pressure,datefrom$table ORDER BY out_pressure DESC LIMIT 1;echo$Max_日期;mysql\u query没有从表中返回数据,您必须使用mysql\u fetch\u XXX或mysql\u result来获取数据。很抱歉造成混乱。我不能在不应用消息的情况下按回车键,奇怪!我写道:$Max_date=mysql_querySELECT out_pressure,datefrom$table ORDER BY out_pressure DESC LIMIT 1;echo$Max_日期;这给了我一个资源id,你不能在注释中放入格式化文本。把它加到问题上。