ID: 35103
Updated by: [EMAIL PROTECTED]
Reported By: php at pjberkel dot com
-Status: Assigned
+Status: Feedback
Bug Type: MySQLi related
Operating System: *
PHP Version: 5CVS-2005-11-04 (cvs)
Assigned To: andrey
New Comment:
Hi,
this has been addressed in the 5.1 branch. So far HEAD (6.0) is not
patched, neither 5.0. Fixed is that a value from PS if the platform is
32bit and the type is int(11) unsigned and if the value is > MAX_INT a
string will be returned. If the value <= MAX_INT an int will be
returned. I know it's not nice to have different types but these are
the limitations of PHP. In year or 2 most servers will run on 64bit :)
Regarding the types returned. mysqli_query() always returns strings
which is not that quite efficient in terms of memory consumption but
the underlying libmysql functions return strings. It's matter of choice
whether this can be optimized (by using more CPU cycles to reduce memory
consumption).
Previous Comments:
------------------------------------------------------------------------
[2005-11-07 08:34:38] php at pjberkel dot com
Thanks for the suggested workaround, while this does patch the problem
it will be preferable to have a permanent fix as updating my entire
codebase to deal with this problem will be quite time-consuming.
Note that mysqli->query() / mysqli->fetch_row() does not appear to
suffer from this bug, changing the prepared statement in the example to
the following code:
$result = $mysqli->query("SELECT id FROM temp");
while ($row = $result->fetch_row()) {
var_dump($row[0]);
}
$result->close();
Shows that the values are correctly returned as variable type string
(show by the results below):
string(10) "2147483647"
string(10) "2147483648"
string(10) "2147483649"
string(10) "3800001532"
string(10) "3900002281"
string(10) "4294967295"
For the sake of consistency, it would be a good idea for both
mysqli->query() and mysqli->prepare() to return the results using the
same variable types.
------------------------------------------------------------------------
[2005-11-05 23:05:41] [EMAIL PROTECTED]
How about using float type if the returned value is > MAX_INT?
------------------------------------------------------------------------
[2005-11-04 15:53:27] [EMAIL PROTECTED]
if your code is aware that the variable is unsigned you can get the
unsigned value by using sprintf() with %u as format specificator
[EMAIL PROTECTED]:~/test> php -r '$a=-2; printf("%d %u\n", $a, $a);'
-2 4294967294
However I think it is good idea to make that implicit so mysqli to
return a string (on 32bit) and normal int (on 64bit).
------------------------------------------------------------------------
[2005-11-04 12:46:29] php at pjberkel dot com
Compiling the current php5 STABLE CVS snapshot version under RHEL 4
yields the same incorrect results as before: using "var_dump" instead
of "print" in the original example gives the results:
int(2147483647)
int(-2147483648)
int(-2147483647)
int(-494965764)
int(-394965015)
int(-1)
------------------------------------------------------------------------
[2005-11-04 11:17:12] php at pjberkel dot com
Description:
------------
When using "mysqli_stmt_bind_result" to retrieve a 32bit unsigned
integer value from a mysql database (version 4.1.13-standard) that is
greater than the maximum *signed* value but less than the maximum
*unsigned* value (i.e. 2147483647 < int <= 4294967295), the integer is
returned incorrectly as a signed value.
I did read in the manual that php does not support unsigned integers
(http://www.php.net/manual/en/language.types.integer.php), however in
this case, mysqli_stmt_bind_result should probably cast the result to a
float.
Reproduce code:
---------------
<?php
$mysqli = new mysqli("host", "user", "pass", "db");
$mysqli->query("CREATE TABLE temp (id INT UNSIGNED NOT NULL)");
$mysqli->query("INSERT INTO temp (id) VALUES
(2147483647),(2147483648),(2147483649),(3800001532),(3900002281),(4294967295)");
/* BEGIN EXAMPLE OF BUG */
$stmt = $mysqli->prepare("SELECT id FROM temp");
$stmt->execute();
$stmt->bind_result($id);
while ($stmt->fetch()) {
print $id . "<br>\n";
}
$stmt->close();
/* END EXAMPLE OF BUG */
$mysqli->query("DROP TABLE temp");
$mysqli->close();
?>
Expected result:
----------------
2147483647
2147483648
2147483649
3800001532
3900002281
4294967295
Actual result:
--------------
2147483647
-2147483648
-2147483647
-494965764
-394965015
-1
------------------------------------------------------------------------
--
Edit this bug report at http://bugs.php.net/?id=35103&edit=1
