PHP Columnar Data (2 Kolom)

<table border="1">
<?php
include "mysqli_connect.php";
$i=1;
$sql = $mysqli->query("SELECT * from tabel where blablabla");
while($data = mysqli_fetch_array($sql)){
    if($i==1) echo "<tr>\n";
    echo "  <td>$data[nama_produk]</td>\n";
    if($i%2==0) echo "</tr>\n<tr>\n";
$i++;
}
?>
</table>