/**
* Save product category relations
*
* @param Mage_Catalog_Model_Product $product
* @return Mage_Catalog_Model_Resource_Eav_Mysql4_Product
*/
protected function _saveCategories(Varien_Object $object)
{
$categoryIds = $object->getCategoryIds();
$oldCategoryIds = $object->getOrigData('category_ids');
$oldCategoryIds = !empty($oldCategoryIds) ? explode(',', $oldCategoryIds) : array();
$object->setIsChangedCategories(false);
$insert = array_diff($categoryIds, $oldCategoryIds);
$delete = array_diff($oldCategoryIds, $categoryIds);
$write = $this->_getWriteAdapter();
if (!empty($insert)) {
$insertSql = array();
foreach ($insert as $v) {
if (!empty($v)) {
$insertSql[] = '(' . (int) $v . ',' . $object->getId() . ',0)';
}
}
if ($insertSql) {
$write->query("insert into {$this->_productCategoryTable}\n (category_id, product_id, position) values " . join(',', $insertSql));
}
}
if (!empty($delete)) {
$write->delete($this->_productCategoryTable, $write->quoteInto('product_id=?', $object->getId()) . ' and ' . $write->quoteInto('category_id in (?)', $delete));
}
if (!empty($insert) || !empty($delete)) {
$object->setIsChangedCategories(true);
}
return $this;
}
