php json_encode mysql result

Question

I have a simple mysql_query and I would like to encode the results(title= > $title, price => $price etc) in json .

$sql = mysql_query("SELECT * FROM item_details WHERE posting_id='$item_number'");
 while($row = mysql_fetch_array($sql))
{
 $title = base64_decode($row['title']);
 $price = $row['price'];
 $seller_user = $row['user'];
}

Answer 1

$sql = mysql_query("SELECT * FROM item_details WHERE posting_id='$item_number'");
$results = array();
while($row = mysql_fetch_array($sql))
{
 $results[] = array(
 'title' => base64_decode($row['title']),
 'price' => $row['price'],
 'seller_user' => $row['user']
 );
}
$json = json_encode($results);