Call to undefined method PDO execute - php

Question

I've get this error on the page. What can be the problem.. I've checked tons of thread here with the same problem and can't figured it out.
$ip_address = $_SERVER['REMOTE_ADDR'];
$vote_rank = 0;
$query = $pdo->prepare("SELECT SUM(vote_rank) as vote_rank FROM ipaddress_vote_map WHERE image_id = ? and ip_address = ?");
$query -> bindParam(1, $_GET['image_id'], PDO::PARAM_INT);
$query -> bindParam(1, $ip_address, PDO::PARAM_INT);
$rowsa = $pdo->execute();
$up = "";
$down = "";
if(!empty($rowsa[0]["vote_rank"])) {
$vote_rank = $row[0]["vote_rank"];
if($vote_rank == -1) {
$up = "enabled";
$down = "disabled";
}
if($vote_rank == 1) {
$up = "disabled";
$down = "enabled";
}
}

Answer 1

Prepare returns the object you need to execute so your code should be:
$stmt= $pdo->prepare("SELECT SUM(vote_rank) as vote_rank FROM ipaddress_vote_map WHERE image_id = ? and ip_address = ?");
$stmt-> bindParam(1, $_GET['image_id'], PDO::PARAM_INT);
$stmt-> bindParam(2, $ip_address, PDO::PARAM_INT);
$rowsa = $stmt->execute();

Answer 2

execute is a method of the PDOStatement class (see docs), not of PDO. The return value of PDO::prepare is an instance of PDOStatement, so replace $pdo->execute(); with $query->execute();
The bindParam calls also seem incorrect to me, as the docs say on the first argument ($parameter):
Parameter identifier. For a prepared statement using named placeholders, this will be a parameter name of the form :name. For a prepared statement using question mark placeholders, this will be the 1-indexed position of the parameter.
This means that this:
$query -> bindParam(1, $_GET['image_id'], PDO::PARAM_INT);
$query -> bindParam(1, $ip_address, PDO::PARAM_INT);
Should be:
$query->bindParam(1, $_GET['image_id'], PDO::PARAM_INT);
$query->bindParam(2, $ip_address, PDO::PARAM_INT);