php判断mysql是否为空

<?php
// 数据库连接配置
$host = 'localhost';
$dbname = 'your_database';
$user = 'your_username';
$pass = 'your_password';

try {
    // 创建PDO实例
    $pdo = new PDO("mysql:host=$host;dbname=$dbname;charset=utf8", $user, $password);

    // 执行查询
    $sql = "SELECT * FROM your_table WHERE some_condition";
    $stmt = $pdo->query($sql);

    // 判断结果集是否为空
    if ($stmt->rowCount() > 0) {
        echo "查询结果不为空";
    } else {
        echo "查询结果为空";
    }
} catch (PDOException $e) {
    echo "数据库连接失败: " . $e->getMessage();
}
?>