MySQL表值等于php var（然后显示它）

Question

我有以下MySQL表，我想做到RVR11（500）与php var $ RVR11相等

我有此代码，但是它不起作用。

$servername = "localhost";
$username = "root";
$password = "";


$conn = new mysqli($servername, $username, $password);


if ($conn->connect_error) {
    die("Connection failed: " . $conn->connect_error);
} 
echo "Connected successfully";


$price = mysql_query("SELECT RVR11 FROM tablename");
$result = mysql_fetch_array($RVR11);
echo $result['RVR11'];

很抱歉这个初学者的问题。

Answer 1

您应该在进行任何查询之前选择一个数据库，您可以将第四个参数传递给# since first letter is not a number you can use substring MyModel.objects.all().extra({ 'unsigned_desc': "CAST(substring(desc, 2) AS UNSIGNED)" }).order_by('unsigned_desc') 构造函数。