后台 -- mysql如何写where条件查询

用where查找数据；

<?php
$dbhost = 'localhost:3306';  // mysql服务器主机地址
$dbuser = 'root';            // mysql用户名
$dbpass = 'root';          // mysql用户名密码
$conn = mysqli_connect($dbhost, $dbuser, $dbpass);
if(! $conn )
{
    die('连接失败: ' . mysqli_error($conn));
}
// 设置编码，防止中文乱码
mysqli_query($conn , "set names utf8");
 
$where = '11507阿坤';
$sql = "select * from status where name = '$where' ";//要加单引号包着变量
 
mysqli_select_db( $conn, 'test' );
$retval = mysqli_query( $conn, $sql );
if(! $retval )
{
    die('无法读取数据: ' . mysqli_error($conn));
}
echo '<h2>菜鸟教程 mysqli_fetch_array 测试</h2>';
echo '<table border="1"><tr><td> ID</td><td>年龄</td><td>班级</td><td>性别</td><td>名字</td></tr>';
while($row = mysqli_fetch_array($retval, MYSQLI_ASSOC))
{
    echo "<tr><td> {$row['id']}</td> ".
         "<td>{$row['age']} </td> ".
         "<td>{$row['class']} </td> ".
         "<td>{$row['gender']} </td> ".
         "<td>{$row['name']} </td> ".
         "</tr>";
}
echo '</table>';
mysqli_close($conn);
?>