在mysqli中添加所有重复的值

$servername = "数据库服务器地址";
$username = "用户名";
$password = "密码";
$dbname = "数据库名";

$conn = mysqli_connect($servername, $username, $password, $dbname);
if (!$conn) {
    die("连接失败: " . mysqli_connect_error());
}

$sql = "INSERT INTO 目标表名 (列1, 列2, 列3)
        SELECT 列1, 列2, 列3
        FROM 源表名
        WHERE 列1 IN (
            SELECT 列1
            FROM 源表名
            GROUP BY 列1
            HAVING COUNT(*) > 1
        )";

if (mysqli_query($conn, $sql)) {
    echo "重复的值已成功添加到数据库中";
} else {
    echo "添加重复的值时出错: " . mysqli_error($conn);
}

mysqli_close($conn);