phpsql过滤空值

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

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

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

// 过滤空值
$name = isset($_POST['name']) && !empty($_POST['name']) ? $_POST['name'] : null;
$email = isset($_POST['email']) && !empty($_POST['email']) ? $_POST['email'] : null;

if ($name && $email) {
    $sql = "INSERT INTO users (name, email) VALUES ('$name', '$email')";
    if ($conn->query($sql) === TRUE) {
        echo "新记录插入成功";
    } else {
        echo "Error: " . $sql . "<br>" . $conn->error;
    }
} else {
    echo "姓名和邮箱不能为空";
}

$conn->close();
?>

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

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

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

$sql = "SELECT name, email FROM users WHERE name IS NOT NULL AND email IS NOT NULL";
$result = $conn->query($sql);

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

$conn->close();
?>

$stmt = $conn->prepare("INSERT INTO users (name, email) VALUES (?, ?)");
$stmt->bind_param("ss", $name, $email);
$stmt->execute();

CREATE INDEX idx_name ON users (name);
CREATE INDEX idx_email ON users (email);

CREATE TABLE users (
    id INT(6) UNSIGNED AUTO_INCREMENT PRIMARY KEY,
    name VARCHAR(30) NOT NULL,
    email VARCHAR(50) NOT NULL
);