Duplicate ID issue when trying to copy table row

[EarthDay]

Hello all,

I am trying to create a script to allow me to copy a table row from one database to another but I am having an issue creating new ID's when a duplicate is found. It just tells me that the ID has already been copied if found in the second database. This is also a safety feature to avoid data been over written.

URL is page.php?id=12

The column for ID is set to AI.

$mysqli = mysqli_connect($databaseHost, $databaseUsername, $databasePassword, $databaseName);
 
$id = $_GET['id'];

$sql="select * from db2.contacts where ($id = intval($id));";//  check id is already copied

$res=mysqli_query($mysqli,$sql);

if (mysqli_num_rows($res) > 0) {
$row = mysqli_fetch_assoc($res);
if($id==$row['id'])
{
echo "Already copied"; //error message if already copied

}

} else{

$query=mysqli_query($mysqli,"INSERT INTO db2.contacts SELECT * FROM  db1.contacts WHERE id =$id");

echo "Successfully copied";
}

Any help would be gratefully appreciated as I am banging my head against the table lol

Cheers.

 

[MeMate]

Is id also the auto increment field? If yes, than there's your problem.