Q:

pdo connection wont close once statements have been executed

Using PHP 5.5, I've noticed that I cannot close PDO connections after I've already executed statements using a connection.
For instance:
$dbh = new PDO('mysql:host=localhost;dbname=test', $user, $pass);
$dbh = null;

Closes the connection just fine.  But I can't get the following connection to close here:
$dbh = new PDO('mysql:host=localhost;dbname=test', $user, $pass);
$stmt = $dbh->prepare("select * from someTable where 1<>0");
$stmt->execute();
$dbh = null;

A:

You can see a related note about this on the PHP docs here http://php.net/manual/en/pdo.connections.php#114822.  In short, you need to set the statement and the connection to null.
$stmt = null;
$dbh = null; 

