Question

I am having a bit of a problem binding a value with PDO and PHP. When I replace the values with variables the script returns the proper result but for some reason I can’t get this to work.

// Connect to database in function on different page
function db1() {
    try {
        $pdo = new PDO("mysql:host=localhost;dbname=**********", '**********', '**********');
        $pdo->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION); 
        return $pdo;
        $pdo = null;
    } catch (PDOException $e) {
        die($e->getMessage());
    }
}

// Scrit with problems
$db = db1();
$query = $db->prepare("SELECT column1, column2, column3, column4 FROM table_name WHERE (column4=2 OR column4=3) AND column5=:col1 AND column6=:col2"); // Prepare the statement to prevent any SQL injection
    $query->bindValue(':col1', $var1, PDO::PARAM_INT);
    $query->bindValue(':col2', $var2, PDO::PARAM_STR);
    $query->execute();
// I also tried the following.
// $query->execute(array(':col1' => $var1, ':col2' => $var2));

// Fetch result row
$row = $query->fetch(PDO::FETCH_ASSOC);

Any ideas?

---

UPDATE
Did var_dump before and after the query. var1 = string(1) “2” and var2 = string(1) “1”

Removed $pdo = null;

Answer 1

Except for the $pdo = null line which is after a return and therefore never executed, and the $db = $db1() where the function is used as a variable, the code hasn’t anything obviously wrong. Since you say that replacing the bindings with variables work, I assume the last is a typo.

So I suggest you try and var_dump what the values of $var1 and $var2 are at that point in the script.

UPDATE

I have duplicated the setup like this

<?php

    $db = new PDO("mysql:host=localhost;dbname=test");
    $db->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);

    $var1 = 1; // See answer text below
    $var2 = 2;

    $query = $db->prepare("SELECT * FROM test WHERE column5=:col1 AND column6=:col2");
    $query->bindValue(':col1', $var1, PDO::PARAM_INT);
    $query->bindValue(':col2', $var2, PDO::PARAM_STR);
    $query->execute();
    $row = $query->fetch(PDO::FETCH_ASSOC);
    print_r($row);
?>

Then I created a first table like this

CREATE TABLE test ( column5 INTEGER, column6 INTEGER );

and then like this

CREATE TABLE test ( column5 varchar(5), column6 varchar(5) );

and I tried defining $var1 and $var2 as 1,2 (integer) and “1”,”2″ (strings).

It always worked, i.e., I expected to get a single row as output, and I did:

Array
(
   [column5] => 1
   [column6] => 2
)

At this point I think the only possibility left is something strange in the database content.

Therefore I also expect the test below, on your system, not to work, i.e. not to return the desired row:

$query = $db->prepare("SELECT column1, column2, column3, column4 FROM table_name WHERE (column4=2 OR column4=3) AND column5=2 AND column6='1'");
$query->execute();
$row = $query->fetch(PDO::FETCH_ASSOC);
var_dump($row);