Join with zend_db_table_abstract classes in Zend Framework

Question

I have a module with two models that extend Zend_Db_Table_Abstract:

class Departments_Model_Subpages extends Zend_Db_Table_Abstract
{
    protected $_name = 'bktg_departments_subpages';
    protected $_primary = 'id';
}

class Departments_Model_Departments extends Zend_Db_Table_Abstract
{
    protected $_name = 'bktg_departments';
    protected $_primary = 'id';
}

Reading through the documentation, what I want to do is something like this (obviously, wrong):

$depTable = new Departments_Model_Departments();
$subTable = new Departments_Model_Subpages();

$depQuery = $depTable->select()->setIntegrityCheck(false)
->from($depTable, array('id', 'title'))
->join($subTable, array('COUNT(id) as `count`'))
->where('bktg_departments.id = bktg_departments_subpages.parent_id');

What am I missing? I just can't wrap my head around Zend joins, and I'm thinking I'm going to end up writing straight sql.

Thank you for having a look.

Edit

Here's what I'm working with now:

$depQuery = $depTable->select()->setIntegrityCheck(false)
->from($depTable, array('id', 'title'))
->joinLeft($subTable, 'bktg_departments.id = bktg_departments_subpages.parent_id',       array('COUNT(id) as count'))
->order('id DESC')
->group('id');

The sql that works for me:

SELECT bktg_departments.id, bktg_departments.title, count(bktg_departments_subpages.id) FROM bktg_departments left join bktg_departments_subpages on bktg_departments.id = bktg_departments_subpages.parent_id group by bktg_departments.id

And I am having issues reproducing that in Zend.

Answer 1

As far as I can tell, passing an object into the table parameter doesn't give you the expected results, and always generates an error. Even a method such as $table->getName() generates errors so I was forced to type out the name manually. I don't know if I was expecting more out of the select object then it's capable of or this is a bug in 1.11. Either way, I hope this helps someone with their frustrations.

The following code works:

$depQuery = $depTable->select()->setIntegrityCheck(false)
->from($depTable, array('id', 'title'))
->joinLeft('bktg_departments_subpages', 'bktg_departments.id = bktg_departments_subpages.parent_id', array('count' => 'COUNT(bktg_departments_subpages.id)'))
->group('bktg_departments.id')
->order('bktg_departments.id DESC');