Does PDO bindParam provide non-existent variables?

Question

As during development, I set error_reporting(-1); , so I was sure that every syntax error would be shown by PHP. This, for example,

 echo $ttt; 

of course he gives

 Notice: Undefined variable: ttt in ... 

In this code snippet (part of some class representing a row in a mysql table):

 public function delete(){ // ... $sth=$dbh->prepare('DELETE FROM tobjects WHERE IdObject=:id'); $sth->bindParam(':id',$this->fid,PDO::PARAM_INT); $sth->execute(); 

I was mistaken that now $this->fid , and the deletion did not happen, the error was not even noticed, and I spent a lot of time to find it.

$dbh set elsewhere as:

 $dbh=new PDO("mysql:host=XXXX;port=XXXX;dbname=XXXX",$db_user, $db_password,array(PDO::MYSQL_ATTR_INIT_COMMAND => 'SET NAMES \'UTF8\'')); $dbh->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION); 

Am I doing something wrong or how is it possible that no error was given?

Answer 1

You do not see a notification because the arguments of bindParam are passed as a reference.

 function test(&$var) { // var may also be undefined var_dump($var); } test($undef); 

This does not cause any errors. Doc: What links are