Find text in database and insert results in same database

hello friends , here the code i did,
the output is like http://www.domain.com/rai/2037/play.php
and i want to insert this url and overwrite any existing value

<?php
$servername = "localhost";
$username = "root";
$password = "root";
$dbname = "tube";
// Create connection
$conn = new mysqli($servername, $username, $password, $dbname);
// Check connection
if ($conn->connect_error) {
    die("Connection failed: " . $conn->connect_error);
}
$sql = "SELECT video FROM videos WHERE video LIKE '%rai%'";
$result = $conn->query($sql);
if ($result->num_rows > 0) {
    // output data of each row
    while($row = $result->fetch_assoc()) {
     
        preg_match('/(http:\/\/www.domain.com\/rai\/)(.*play.php)/', $row["video"], $link);
        if (empty($link[0])) {
    echo "Nothing found!";
} else {
    echo $link[0];
}
    }
}
$conn->close();
?>

PHP:

here i want to replace $row["video"] value with $link[0]

thanks for any help

 

} else {
    echo $link[0];
    $conn->query('UPDATE videos SET video ="'.$link[0].'" WHERE video ="'.$row['video'].'"');
}

PHP: