Copy the attachment of one WP to another WP

copy-attachement.php

<?php
$servername = "YOUR_SERVER_NAME";
$username = "YOUR_USERNAME";
$password = "YOUR_PASSWORD";

// Create connection
$conn = mysqli_connect($servername, $username, $password);

// Check connection
if (!$conn) {
    die("Connection failed: " . mysqli_connect_error());
}

$fromDatabase = 'DATABASE_ONE';
$fromTablePost = $fromDatabase . '.wp_posts';
$fromTablePostMeta = $fromDatabase.'.wp_postmeta';

$toDatabase = 'DATABASE_TWO';
$toTablePost = $toDatabase .'.wp_posts';
$toTablePostMeta = $toDatabase .'.wp_postmeta';

$sql = "SELECT * FROM $fromTablePost WHERE post_type = 'attachment'";
$result = $conn->query($sql);

if($result->num_rows > 0 ){
    // output data of each row
    while($row = $result->fetch_assoc()) {
        $postID = $row['ID'];
        $newRow = make_data($row,'ID',$conn);
        // Insert Data into Post Table
        $inserted_id = insert($conn, $toTablePost, $newRow);
        
        // Collect data from PostMeta
        $sql2 = "SELECT * FROM $fromTablePostMeta WHERE post_id = $postID";
        $result2 = $conn->query($sql2);
        if($result->num_rows > 0 ){

            // output data of each row
            while($row2 = $result2->fetch_assoc()) {
                $newRow2 = make_data($row2,'meta_id', $conn);
                $newRow2['post_id'] = $inserted_id;
                // Insert Data into Post Meta
                insert($conn, $toTablePostMeta, $newRow2);
            }
        }
    }
}
$conn->close();

function insert($db, $table = 'posts', $data = array())
{

	$columns = implode(", ", array_keys($data));
	$escaped_values = array_values($data);
	$values = implode(", ", $escaped_values);
	$sql = "INSERT INTO $table ($columns) VALUES ($values)";

	if ($db->query($sql) === true) {
		return mysqli_insert_id($db);
	} else {
		echo "Error: " . $sql . "<br>" . $db->error;
	}
}

function make_data($row=array(), $key_to_exclude='ID', $conn){
    $newRow = array();
    foreach($row as $key => $value){
        if($key == $key_to_exclude)  continue;

        if(!ctype_digit($value)){
            $newRow[$key] = "'" . mysqli_real_escape_string($conn,$value) . "'";
        }else{
            $newRow[$key] = $value;
        }
    }
    return $newRow;
}
?>