gistfile1.php

<?php

public function search(array $search = NULL, $sort = null, $order = "ASC", $limit = 10) {
  $params = array();
  $values = array();
  // create query builder
  $ns = 's';
  $qb = $this->createQueryBuilder($ns);
  // build parameter bag
  if ($search) {
    foreach ($search as $column => $value) {
      if (is_array($value)) {
        $params[] = sprintf('%s.%s IN (:%s)', $ns, $column, $column);
      } else {
        $params[] = sprintf('%s.%s = :%s', $ns, $column, $column);
      }
      $values[$column] = $value;
    }
  }
  // build where statement (only when necessary)
  if (sizeof($params) > 0) {
    $qb->where(join(' AND ', $params)); // you can change this to use expr() if you want
    foreach ($values as $param => $value) {
      $qb->setParameter($param, $value);
    }
  }
  // add sort parameters
  if (!is_null($sort)) {
    $sortBy = sprintf('%s.%s', $ns, $sort);
    $qb->orderBy($sortBy, $order);
  }
  // add query limit
  $qb->setMaxResults($limit);
  // build query
  $query = $qb->getQuery();
  
  return $query->getResult();
}

Then you'd use it as

$repository->search(array('university' => 10));

or

$repository->search(array('name' => 'My University Name'));

or

$repository->search();