ID: 44409
Updated by: dav...@php.net
Reported By: uwendel at mysql dot com
Status: Open
Bug Type: PDO related
Operating System: *
PHP Version: 5.3CVS-2008-03-11 (CVS)
New Comment:
Hmm is it supposed to say: PDO::FETCH_SERIZALIZE?
Previous Comments:
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[2008-03-11 19:53:48] uwendel at mysql dot com
Description:
------------
There seems to be very few documentation about PDO::FETCH_SERIALIZE in
the PHP manual but playing the guessing game from the code it seems that
this feature aims to support SPL/Serialize interface. As I'm not sure
about the purpose of PDO::FETCH_SERIALIZE I'm not sure if the following
is a bug or not. However, it seems to me that PDO::FETCH_SERIALIZE
unintentionally calls __construct().
One of the main ideas behind SPL/Serialize interface seems to be that
for unserialization the constructor of a class does not get called. The
constructor of a class has a different meaning than a helper function
like unserialize() and thus should not be called automatically. Let's
check:
class myclass implements Serialize {
public function __construct() {
printf("%s()\n", __METHOD__);
}
public function serialize() {
printf("%s()\n", __METHOD__);
return "any data from serialize()";
}
public function unserialize($dat) {
printf("%s(%s)\n", __METHOD__, var_export($dat, true));
}
}
$obj1 = new myclass()
---> myclass::__construct()
$tmp = serialize($obj1)
$obj2 = unserialize($tmp)
---> myclass::unserialize('any data from serizalize()')
__construct() gets called only once for object creation but not again
during unserialization. Let's try that with PDO:
[...]
$stmt = $db->query("SELECT dat FROM test");
$rows = $stmt->fetchAll(PDO::FETCH_CLASS|PDO::FETCH_SERIZALIZE,
"myclass");
--> myclass::unserialize("data from DB")
--> myclass::__construct()
[...]
PDO first calls unserialize() as its supposed to do. But then it also
calls __construct() which is against the idea of the Serialize interface
not to call the constructor automatically during unserialization.
Reproduce code:
---------------
sapi/cli/php -r '$db = new PDO("sqlite:/tmp/foo"); $db->exec("DROP
TABLE test"); $db->exec("CREATE TABLE test(dat VARCHAR(100))");
$db->exec("INSERT INTO test(dat) VALUES (\"Data from DB\")"); class
myclass implements Serializable { public function __construct() {
printf("%s()\n", __METHOD__); } public function serialize() { return
"any data from serizalize()"; } public function unserialize($dat) {
printf("%s(%s)\n", __METHOD__, var_export($dat, true)); }} $stmt =
$db->query("SELECT * FROM test");
var_dump($stmt->fetchAll(PDO::FETCH_CLASS|PDO::FETCH_SERIALIZE,
"myclass")); $obj = new myclass();
var_dump(unserialize(serialize($obj)));'
myclass::unserialize('Data from DB')
myclass::__construct()
array(1) {
[0]=>
object(myclass)#3 (0) {
}
}
myclass::__construct()
myclass::unserialize('any data from serizalize()')
object(myclass)#4 (0) {
}
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--
Edit this bug report at http://bugs.php.net/?id=44409&edit=1
