SQL Server DATEADD function not working with PDO Sqlsrv extension - sql-server

Question

I am using PDO with Sqlsrv extension to connect to a SQL Server database. This query works fine when I run it in any SQL Server database client but in PHP source code it does not produce result.
SELECT session
FROM t_php_session
WHERE php_session_id = 'p64aqbh15u6t35tq2h8n0bluq0'
AND user_ip = '127000000001'
AND DATEADD(MINUTE, 30, created) >= GETDATE()
While debugging I observed that when I remove the DATEADD condition from the WHERE clause, then it works fine and return the result. But I am not sure what is wrong with this condition.
Here is my sample source code:
$session_id = 'p64aqbh15u6t35tq2h8n0bluq0';
$interval = 30;
$ip = '127000000001';
$query = "SELECT session FROM t_php_session WHERE php_session_id = ? AND user_ip = ? AND DATEADD(MINUTE, ?, created) >= GETDATE()";
$stmt = $conn->prepare($query);
$stmt->execute(array($session_id, $ip, $interval));
$result = $stmt->fetchAll();
echo "<pre>";
print_r($result);
This is my SQL Server database table structure:
I also tried assigning values by using bindParam method instead of passing an array in execute statement but that could not work too.
SOLUTION
After getting solution from #Your Common Sense i made following changes and it worked.
$query = "SELECT session FROM t_php_session WHERE php_session_id = ? AND user_ip = ? AND DATEADD(MINUTE, ?, created) >= GETDATE()";
$stmt = $conn->prepare($query);
$stmt->bindParam(1, $session_id, PDO::PARAM_STR);
$stmt->bindParam(3, $interval, PDO::PARAM_INT);
$stmt->bindParam(2, $ip, PDO::PARAM_STR);
$stmt->execute();
$result = $stmt->fetchAll();

Answer 1

The other answer obviously makes the whole idea of prepared statements spoiled.
Your code should positively work, if you bind a number using PDO::PARAM_INT.
At least in emulation mode this would work.