CakePHP - Pagination total count differs from actual count when using DISTINCT - php

Question

I have a find method that uses a DISTINCT clause to get results from my Model. The Controller code looks like below
$options = array(
'limit' => 10,
'fields' => array(
'DISTINCT id', 'title',
),
'contain' => array(
'Dealer' => array('id'),
),
'paramType' => 'querystring'
);
$this->Paginator->settings = $options;
$cars = $this->Paginator->paginate('Car'); // returns 6 distinct rows
The above query return 6 distinct rows and 12 total rows. So when I am displaying, the screen shows 6 distinct rows
However in the View, when I use
echo $this->Paginator->param('count'); // returns 12
I get a count of 12
I checked the SQL Log and noticed that the count query is not using the distinct clause. Any idea how I can override the Paginator count query to use the DISTINCT clause?

Answer 1

Found the solution,
In controller add distinct as an array parameter with other pagination options. So if I was trying to retrieve a list of Cars in my inventory with 10 cars at a time, the options would have a DISTINCT clause in the fields parameter and a separate parameter called distinct would also be added as shown below
$options = array(
'conditions' => $conditions,
'joins' => $joins,
'limit' => 10,
'fields' => array(
'DISTINCT Car.id', 'title', 'user_id'),
'contain' => array(
'Dealer' => array('id'),
),
'paramType' => 'querystring',
'distinct' => 'Car.id'
);
$this->Paginator->settings = $options;
$cars = $this->Paginator->paginate('Car');
In Model, use the below function to override the original paginateCount method
public function paginateCount($conditions = null, $recursive = 0, $extra = array()) {
$parameters = compact('conditions', 'recursive');
if (isset($extra['distinct'])) {
$parameters['fields'] = 'DISTINCT ' . $extra['distinct'];
$count = $this->find('count', array_merge($parameters, $extra));
} else {
// regular pagination
$count = $this->find('count', array_merge($parameters, $extra));
}
return $count;
}
No change in View