PHP の下部にある効率的なデータ ストレージと実装方法

<?php
// 连接数据库
$conn = mysqli_connect("localhost", "username", "password", "database");

// 插入数据
$sql = "INSERT INTO users (name, age, email) VALUES ('John', 25, 'john@example.com')";
$result = mysqli_query($conn, $sql);

// 查询数据
$sql = "SELECT * FROM users WHERE age > 20";
$result = mysqli_query($conn, $sql);
while ($row = mysqli_fetch_assoc($result)) {
    echo $row['name'] . " - " . $row['age'] . " - " . $row['email'] . "<br>";
}

// 关闭数据库连接
mysqli_close($conn);
?>

<?php
// 写入数据
$file = fopen("data.txt", "a");
fwrite($file, "Hello, World!");
fclose($file);

// 读取数据
$file = fopen("data.txt", "r");
$data = fread($file, filesize("data.txt"));
fclose($file);
echo $data;
?>

<?php
// 连接Memcached服务器
$memcached = new Memcached();
$memcached->addServer("localhost", 11211);

// 写入缓存
$memcached->set("key", "value", 60);

// 读取缓存
$value = $memcached->get("key");
echo $value;
?>

<?php
// 连接Redis服务器
$redis = new Redis();
$redis->connect("localhost", 6379);

// 添加分数
$redis->zAdd("leaderboard", 100, "John");
$redis->zAdd("leaderboard", 200, "Amy");
$redis->zAdd("leaderboard", 300, "Tom");

// 获取排行榜前三
$leaders = $redis->zRevRange("leaderboard", 0, 2, true);
foreach ($leaders as $name => $score) {
    echo $name . " - " . $score . "<br>";
}
?>