using group() breaks getSelectCountSql in magento - magento

Question

When I'm using
$collection->getSelect()->group('entity_id')
or
$collection->groupByAttribute('entity_id')
It breaks getSelectCountSql and I'm getting 1 record and 1 page.
Magento does
$countSelect->columns('COUNT(DISTINCT e.entity_id)');
Is there a way to fix it?
I run into it,While overriding _prepareCollection of Mage_Adminhtml_Block_Catalog_Product_Grid
Thanks

Answer 1

I updated the lib/Varien/Data/Collection/Db.php file to allow this as I had to have it work. You'll have to keep track of this for upgrades but it works.
public function getSelectCountSql()
{
$this->_renderFilters();
$countSelect = clone $this->getSelect();
$countSelect->reset(Zend_Db_Select::ORDER);
$countSelect->reset(Zend_Db_Select::LIMIT_COUNT);
$countSelect->reset(Zend_Db_Select::LIMIT_OFFSET);
$countSelect->reset(Zend_Db_Select::COLUMNS);
// Count doesn't work with group by columns keep the group by
if(count($this->getSelect()->getPart(Zend_Db_Select::GROUP)) > 0) {
$countSelect->reset(Zend_Db_Select::GROUP);
$countSelect->distinct(true);
$group = $this->getSelect()->getPart(Zend_Db_Select::GROUP);
$countSelect->columns("COUNT(DISTINCT ".implode(", ", $group).")");
} else {
$countSelect->columns('COUNT(*)');
}
return $countSelect;
}

Answer 2

in some cases, the method from Eric doesn't work.
It's better to rewrite the getSize() method to
public function getSize()
{
if (is_null($this->_totalRecords)) {
$sql = $this->getSelectCountSql();
$result = $this->getConnection()->fetchAll($sql, $this->_bindParams);;
foreach ($result as $row) {
$this->_totalRecords += reset($row);
}
}
return intval($this->_totalRecords);
}

Answer 3

I have solved this using the function below:
public function getSize()
{
return sizeof( $this->getAllIds());
}
This helped me in issue of getSize() returning 1 count of product collection in Magento CE 1.5.
I have overwritten the Mage_Catalog_Model_Resource_Eav_Mysql4_Product_Collection file and place above function.

Answer 4

Very nice article
Here are few changes I made in order to make it work for me
Changes suggested in Db.php are not required for resolving group by in catalog collection.
I made the similar change in
Catalog->model->Ressource->EAV->Mysql4->product->collection.php
Here is the code I added to getSelectCountSql()
if(count($this->getSelect()->getPart(Zend_Db_Select::GROUP)) > 0) { $countSelect->reset(Zend_Db_Select::GROUP); }
After this things get resolved but a new issue comes in .. In Layered navigation quantities for all the filters is 1.

Answer 5

I made it without touching Core files by overriding the getSize() method of my collection.
public function getSize()
{
if (count($this->getSelect()->getPart(Zend_Db_Select::GROUP)) > 0) {
// Create a new collection from ids because we need a fresh select
$ids = $this->getAllIds();
$new_coll = Mage::getModel('module_key/model')->getCollection()
->addFieldToFilter('id', array('in' => $ids));
// return the collection size
return $new_coll->getSize();
}
return parent::getSize();
}
Tell me if that works for you..
Bouni