Disconnect a PHP PDO connection to RDBMS

PHP's PDO connection management is a bit arcade. It does not offer an explicit way to disconnect from database. Here is the PHP's documentation:

http://php.net/manual/en/pdo.connections.php

Inside which it will tell you to set the variable that holds the PDO connection object to null. However the catch is you also need to set all other objects which might hold reference to the PDO object to null as well, and it can be cumbersome as expressed in the comments section of that page. Here is an example: $dbh = new PDO('mysql:host=localhost;dbname=test', $user, $pass); // use the connection here, note the side effect of // a new $sth reference to the PDO $sth = $dbh->query('SELECT * FROM foo'); // and now we're done; close both $sth and $dbh ! $sth = null; // this is not obvious $dbh = null; Enjoy!