Magento Sales Order Grid Joining Table

I am wondering if anyone out there has had much luck joining the order items table to the sale order grid and being able to filter correctly?

I have already been able to complete the join, like so:

protected function _prepareCollection()
{
    parent::_prepareCollection();

    $collection = Mage::getResourceModel($this->_getCollectionClass())
    ->join(
        'sales/order_item',
        '`sales/order_item`.order_id=`main_table`.entity_id',
        array(
            'skus'  => new Zend_Db_Expr('group_concat(`sales/order_item`.sku SEPARATOR ",")'),
            'names' => new Zend_Db_Expr('group_concat(`sales/order_item`.name SEPARATOR ",")'),
            )
        );
        $collection->getSelect()->group('entity_id');

    $this->setCollection($collection);

    return Mage_Adminhtml_Block_Widget_Grid::_prepareCollection();
}

But I am now trying to add the column filter like so:

protected function _addColumnFilterToCollection($column)
{
    if($this->getCollection() && $column->getFilter()->getValue()) 
    {
        if($column->getId() == 'skus')
        {
            $this->getCollection()->join(
                'sales/order_item',
                '`sales/order_item`.order_id=`main_table`.entity_id',
                array(
        开发者_Python百科            'skus'  => new Zend_Db_Expr('group_concat(`sales/order_item`.sku SEPARATOR "|")'),
                )
            )->getSelect()
                ->group('`main_table`.entity_id')
                ->having('find_in_set(?, `main_table`.skus)', $column->getFilter()->getValue());

            return $this;
        }
        if($column->getId() == 'names')
        {

            $this->getCollection()->join(
                'sales/order_item',
                '`sales/order_item`.order_id=`main_table`.entity_id',
                array(
                    'names' => new Zend_Db_Expr('group_concat(`sales/order_item`.name SEPARATOR ",")'),
                )
            )->getSelect()
                ->group('`main_table`.entity_id')
                ->having('find_in_set(?, names)', $column->getFilter()->getValue());

            return $this;
        }
    }
    return parent::_addColumnFilterToCollection($column);
}   

Each time I try to filter I get this error: "Column not found: 1054 Unknown column 'main_table.names' in 'having clause...".

Please let me know if you have experienced this before and it you have any pointers?

I had the same problem, when i took al closer look at the problem I did see that the pagination query was causing the error. Alter the getSelectCountSql() in your model, add the following

$countSelect->reset(Zend_Db_Select::HAVING);

Your page will be shown, but you have to alter the getSelectCountSql() tot get the correct number of pages and results.