php数组 mysql

// 索引数组
$numbers = array(1, 2, 3, 4, 5);

// 关联数组
$students = array(
    "Alice" => 20,
    "Bob" => 22,
    "Charlie" => 21
);

// 访问数组元素
echo $numbers[0]; // 输出: 1
echo $students["Alice"]; // 输出: 20

// 遍历数组
foreach ($numbers as $num) {
    echo $num . " ";
}
echo "\n";

foreach ($students as $name => $age) {
    echo $name . ": " . $age . "\n";
}

// 连接数据库
$servername = "localhost";
$username = "username";
$password = "password";
$dbname = "myDB";

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

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

// 插入数据
$sql = "INSERT INTO MyGuests (firstname, lastname, email)
VALUES ('John', 'Doe', 'john@example.com')";

if ($conn->query($sql) === TRUE) {
    echo "新记录插入成功";
} else {
    echo "Error: " . $sql . "<br>" . $conn->error;
}

// 查询数据
$sql = "SELECT id, firstname, lastname FROM MyGuests";
$result = $conn->query($sql);

if ($result->num_rows > 0) {
    while($row = $result->fetch_assoc()) {
        echo "id: " . $row["id"]. " - Name: " . $row["firstname"]. " " . $row["lastname"]. "<br>";
    }
} else {
    echo "0 结果";
}

$conn->close();