Data Mapper Pattern: Complexe query from Service Layer

Question

I'm sing the Data Mapper Pattern in Zend Framework. This works well so far, but now I got to a point where I need your help/opinion. So let's start with the Code:

We got a table with several Persons:

CREATE TABLE `persons` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `name` varchar(50) NOT NULL,
  `age` int(3) NOT NULL,
  `haircolor` varchar(20) DEFAULT NULL,
  PRIMARY KEY (`id``),
);

Now I try to select all people, that have brown hair. I use the following method in the ServiceLayer

public function getPeopleByHaircolor($hair) {
  return $this->getMapper()->fetch('haircolor = ?', $hair);
}

The method in the Mapper looks like this:

public function fetch($condition, $value) {
  $resultSet = $this->getTable()->fetchAll($this->getTable()->select()->where($cond, $value));
  $entries = array();

  foreach($resultSet as $row) {
    $entry = new Default_Model_Person();
    $entry->id   = $row->id;
    $entry->name = $row->name;
    [...]
  }
  return $entries;
}

I think I follow the Data Mapper Pattern with this methods...

Now the Problem:

I want to select Persons, that have brown hair AND that are younger than 20 yrs. So how can I do that? My try:

public function getTeens($hair) {
  $rows = $this->getMapper()->fetch('haircolor = ?', $hair);
  $return = array();
  foreach($rows as $row) {
    if((int)$row->age < 20) $return[] = $row;
  }
  return $return;
}

But if you get more variables, like "people with brown hair, younger than 20yrs and with the name 'Foo Bar'", I need more and more methods and/or foreach loops.

My Question:

How would you do this in the Data Mapper Pattern? If I do a native SQL query like $serviceLayer->mapper->table->qry('SELECT ...'), is this breaking the Data Mapper Pattern? I don't like those additional foreach loops and it feels like I'm doing something wrong, so I wrote this question.

Data Mapper Pattern: Complexe query from Service Layer

2 Answers