Fatal error: Uncaught TypeError: Argument 3 passed to Mage_Catalog_Model_Resource_Abstract::_canUpdateAttribute()

Question

I am getting an error while trying to pragmatically remove products from some categories.

Error:

Fatal error: Uncaught TypeError: Argument 3 passed to Mage_Catalog_Model_Resource_Abstract::_canUpdateAttribute() must be of the type array, null given, called in /xxx/public_html/app/code/core/Mage/Eav/Model/Entity/Abstract.php on line 1225 and defined in /xxx/public_html/app/code/core/Mage/Catalog/Model/Resource/Abstract.php:540

Stack trace: #0 /xxx/public_html/app/code/core/Mage/Eav/Model/Entity/Abstract.php(1225): Mage_Catalog_Model_Resource_Abstract->_canUpdateAttribute(Object(Mage_Catalog_Model_Resource_Eav_Attribute), '2019-01-14 00:0...', NULL)

#1 /xxx/public_html/app/code/core/Mage/Eav/Model/Entity/Abstract.php(1123): Mage_Eav_Model_Entity_Abstract->_collectSaveData(Object(Mage_Catalog_Model_Product))

#2 /xxx/public_html/app/code/core/Mage/Core/Model/Abstract.php(318): Mage_Eav_Model_Entity_Abstract->save(Object(Mage_Catalog_Model_Product))

#3 /home/admin/domains/gr in /xxx/public_html/app/code/core/Mage/Catalog/Model/Resource/Abstract.php on line 540

And my code:

$products = Mage::getModel('catalog/category')->setStoreId($storeId)->load($specialCategoryId)
    ->getProductCollection()
    ->addAttributeToSelect(array('special_to_date', 'category_ids'))
    ->addAttributeToFilter('special_to_date', array('lteq' => date("Y-m-d")));

foreach ($products as $product) {

    $oldCategories = $product->getCategoryIds();
    $newCategories = array_diff($oldCategories, $specialCategoryIds);

    if($oldCategories != $newCategories){
        $_product = Mage::getModel('catalog/product')->load($product->getEntityId());

        $_product->setCategoryIds($newCategories);

        Mage::log('Product ID: ' .$product->getEntityId(), null, 'RemoveFromCategoryLog.log', true);
        try {
            $_product->save();
        } catch(Exception  $e){
            Mage::log($e->getMessage(), null, 'RemoveFromCategoryLog.log', true);
        }
    }
}

Loading the product did not solve it. And as there are lots of products i am reluctant to use category_api.

Answer 1

If using SQL is an option for you, you can delete and add entries in the table catalog_category_product

For example, if you want to delete product with product_id = 1 from category with category_id = 99 use this statement:

delete from catalog_category_product where product_id = 1 and category_id = 99;

To assign the product with product_id = 1 to category with category_id = 77 (on first position) use this statement:

insert into catalog_category_product (category_id,product_id,position) values (77,1,1);

After doing this you need to rebuild the category index and everything is done.

Otherwise consider to use Mage_Catalog_Model_Category_Api and the methods assignProduct and updateProduct. The product model doesn't save the categoryIds you set with setCategoryIds() - since you need a position for the product in a category.

Answer 2

Try by writing this below line of code at the beginning of your custom script

Mage::app()->setCurrentStore(Mage_Core_Model_App::ADMIN_STORE_ID);

Answer 3

My final solution using sql.

resource = Mage::getSingleton('core/resource');
$write = $resource->getConnection('core_write');
$table = 'catalog_category_product';

$write->delete(
    $table,
    array(
      'category_id = ?' => $catId,
      'product_id = ?' => $product->getEntityId()
    )
);

Based on answers from @HelgeB and @Shadowbob in answer Magento 1 SQL Queries