PHP学习笔记：云计算与大数据

<?php
$servername = "localhost";
$username = "username";
$passWord = "password";

// 创建连接
$conn = new Mysqli($servername, $username, $password);

// 检测连接
if ($conn->connect_error) {
    die("连接失败: " . $conn->connect_error);
}
echo "连接成功";
$conn->close();
?>

<?php
$command = "/usr/local/hadoop/bin/hadoop jar /path/to/hadoop-streaming.jar -file /path/to/mapper.php -mapper /path/to/mapper.php -file /path/to/reducer.php -reducer /path/to/reducer.php -input /path/to/input -output /path/to/output";
$output = shell_exec($command);
echo $output;
?>

<?php
$servername = "localhost";
$username = "username";
$password = "password";
$dbname = "database";

// 创建连接
$conn = new mysqli($servername, $username, $password, $dbname);

// 检测连接
if ($conn->connect_error) {
    die("连接失败: " . $conn->connect_error);
}

// 执行sql查询
$sql = "SELECT * FROM users WHERE age > 18";
$result = $conn->query($sql);

if ($result->num_rows > 0) {
    // 输出数据
    while($row = $result->fetch_assoc()) {
        echo "姓名: " . $row["name"]. " 年龄: " . $row["age"]. "<br>";
    }
} else {
    echo "0 结果";
}

$conn->close();
?>