Question

Is it possible for a virtualFields var to be the sum of a field from a linked table?

For example, in, say, an Invoice model, could you have

public $virtualFields = array(
    'invoiceNett' => 'SUM(InvoiceLine.nett)'
);

but obviously only SUMming the lines that belong to that invoice?

Thanks.

== Using CakePHP 2.0

Answer 1

You could use the afterFind callback to get the sum. This avoids storing the calculated values​​, which should be avoided when possible.

function afterFind($results)
{
    foreach($results as &$result)
    {

        /*
        Use something like:

        $this->InvoiceLine->find('all', array('fields'     => array('SUM(InvoiceLine.nett) as total'), 
                                              'conditions' => array('invoice_id' => $result['Invoice']['id'])));
        */
    }
    unset($result);
}