Doctrine Query Builder not registering parameter?

Question

I have the following code which is throwing the exception Invalid parameter number: number of bound variables does not match number of tokens. Yet when I print the registered parameters, my parameter is showing up.

public function getUnitPriceFor($entityType,$entityID,$qty,$configuration_id)
{
    $this->qb = $this->getEntityManager()->createQueryBuilder();
    $this->qb   ->select($this->_entities[$entityType]['select'])
                // for Base this would be ->select(array('t','c','w','g'))
                // for the other cases below, like website, it's array('t','w')
                ->from('AcmeBundle:PriceTier', 't');

    switch($entityType) :
        case 'base' :
            $this->qb   ->leftJoin('t.customers','c')
                        ->leftJoin('t.customergroups','g')
                        ->leftJoin('t.websites','w');
        break;
        case 'website' :
            $this->qb   ->join('t.websites','w','WITH','w.id = '.$entityID);
        break;
        case 'custgrp' :
            $this->qb   ->join('t.customergroups','g','WITH','g.id = '.$entityID);
        break;
        case 'cust' :
            $this->qb   ->join('t.customers','t','WITH','t.id = '.$entityID);
        break;
    endswitch;

    $this->qb           ->where('t.printconfiguration = :configuration_id');
    $this->qb           ->setParameter('configuration_id', $configuration_id);

    print_r( $this->qb->getParameters() );

    $dql = $this->qb->getDQL();

    echo"<pre>";
    print_r($this->getEntityManager()->createQuery($dql)->getArrayResult());
    echo"</pre>";
}

Printing $this->qb->getParameters(); shows me Array ( [configuration_id] => 1 ), and removing my where and set parameter clauses prevents the exception from occurring. Finally, (and get this), if I remove my where clause but keep the parameter set, no exception occurs. I'm rather confused.

Answer 1

Apparently $dql = $this->qb->getDQL(); will not pass parameters.

I needed to change

$dql = $this->qb->getDQL();

echo"<pre>";
print_r($this->getEntityManager()->createQuery($dql)->getArrayResult());
echo"</pre>";

to

$query = $this->qb->getQuery();

echo"<pre>";
print_r($query->getArrayResult());
echo"</pre>";