bigint truncated via PDO?

Question

I came across a problem with storing a large integer in a BIGINT column on MySQL via PDO

If i run this test:

$number = "30123456789";
var_dump($number); //prints string(11) "30123456789"

$new_number = (int)$number;
var_dump($new_number); //prints int(30123456789) 

So far so good...

If I run this SQL directly in MySQL:

update my_table set bigint_field = 30123456789 where id_field = 1

Everything works fine...

The problem arise when I try to save that number via PDO and I reduced the problem to this line of code:

//parameterized query
//update my_table set bigint_field = :bigint_field where id_field = :id_field
$statement->bindValue(":bigint_field", $new_number, PDO::PARAM_INT);

If the optional third type parameter is absent or equals PDO::PARAM_STR then the value is saved jut fine, if not the value is truncated to 58685709. If I try to save 20288976024, the value is truncated to 0. What is happening here

I'm running PHP 5.5.33 and MySQL 5.6.25 on Debian Wheezy x64

Answer 1

I cannot reproduce your case.

On a x86 system intval() already makes 2147483647 On a 64 bit system everything works fine.

Binding bigint values as strings may lead to wrong results, as value will be cast to a float and lose precision.

Edit: it turned out to be an old libmysql issue. Having PHP configured this way I was able to reproduce the problem:

$number     = 30123456789;
$new_number = 20288976024;
var_dump($number, $new_number);

$pdo->query("CREATE TEMPORARY TABLE bint_test(i BIGINT unsigned)");

$pdo->setAttribute(PDO::ATTR_EMULATE_PREPARES, FALSE);

$stmt = $pdo->prepare("insert into bint_test values (?)");
$stmt->bindValue(1, $number, PDO::PARAM_INT);
$stmt->execute();
$stmt->bindValue(1, $new_number, PDO::PARAM_INT);
$stmt->execute();

echo json_encode($pdo->query("SELECT * FROM bint_test")->fetchAll());

prints out

int(30123456789)
int(20288976024)
[{"i":"58685717"},{"i":"0"}

Two possible solutions:

1. (Preferred) Install php-mysqlnd, which you have to do anyway, because mysqlnd is an new replacement for the old libmysql connector.
2. Turn emulation mode ON - a query that is constructed by PDO is also works flawless.