PHP PDO close mysql connection in DatabaseFactory file - php

Question

do you guys have an idea why I can't close the mysql connection?
Here is my code:
class DatabaseFactory {
private static $factory;
private $connection = array(
"DB_HOST" => "localhost",
"DB_PASS" => "*************",
"DB_USER" => "*************",
"DB_PORT" => "3306",
"DB_CHARSET" => "utf8"
);
public static
function getFactory() {
if(!self::$factory) {
self::$factory = new DatabaseFactory();
}
return self::$factory;
}
private $db;
public
function getconnection($name) {
echo "opened";
try {
$options = array(
\PDO::ATTR_DEFAULT_FETCH_MODE => \PDO::FETCH_OBJ,
\PDO::ATTR_ERRMODE => \PDO::ERRMODE_WARNING
);
$this->db = new \PDO('mysql:host='.$this->connection["DB_HOST"].';dbname='.$name.';port=' .$this->connection["DB_PORT"].';charset='.$this->connection["DB_CHARSET"], $this->connection["DB_USER"], $this->connection["DB_PASS"], $options);
} catch (PDOException $e) {
exit($e->getMessage());
}
return $this->db;
}
public
function __destruct() {
echo "closed";
try {
$this->db = null;
unset($this->db);
} catch (PDOException $e) {
exit($e->getMessage());
}
}
}
$database = DatabaseFactory::getFactory()->getconnection("Admin");
$query = $database->prepare("SELECT * FROM tester WHERE t_u_id = :u_id");
$query->execute(array(":u_id" => "281123341528-D050C4-91A0BA-1CB0C8-8112334152855AC373"));
The connection is connecting but it is not closed.
The method __destruct will be called but the mysql total connections count doesn't decrease.

Answer 1

Why don't you implement and call a method (manually instead of relying on __destruct()) like Fil does in his response here?
Add the following static method to your DatabaseFactory class
static function closeConnection(&$conn) {
$conn=null;
}
So after your connections, you can NULL your connection reference (which is akin to calling $mysqli_conn->close();) later in your code like this:
$database = DatabaseFactory::getFactory()->getconnection("Admin");
$query = $database->prepare("SELECT * FROM tester WHERE t_u_id = :u_id");
$query->execute(array(":u_id" => "281123341528-D050C4-91A0BA-1CB0C8-8112334152855AC373"));
DatabaseFactory::closeConnection($database)
EDIT:
Also, I wanted to mention that by relying on __destruct(), you are subject to the following as per the PHP docs:
PHP 5 introduces a destructor concept similar to that of other
object-oriented languages, such as C++. The destructor method will be
called as soon as there are no other references to a particular
object, or in any order during the shutdown sequence.
In regards to your question, the method __destruct() might not be called because the static class var private static $factory is never being nulled. Therefore, the class always has a reference to "itself" preventing __destruct() from being called.
I hope this helps!