Magento 2.1 – addAttributeToSelect Not Working with Product Collection

collection;jsonmagento-2.1product-attributeselect

I am applying these fillers:

$collection->addAttributeToSelect('name');
$collection->addAttributeToSelect('sku');

but every time getting full record as comes form:

$collection->addAttributeToSelect('*');

[{"entity_id":"101","attribute_set_id":"9","type_id":"simple","sku":"MH04-XS-White","has_options":"0","required_options":"0","created_at":"2018-10-08 07:35:50","updated_at":"2018-10-08 07:35:50"},{"entity_id":"102","attribute_set_id":"9","type_id":"simple","sku":"MH04-XS-Yellow","has_options":"0","required_options":"0","created_at":"2018-10-08 07:35:50","updated_at":"2018-10-08 07:35:50"},{"entity_id":"103","attribute_set_id":"9","type_id":"simple","sku":"MH04-S-Green","has_options":"0","required_options":"0","created_at":"2018-10-08 07:35:50","updated_at":"2018-10-08 07:35:50"},{"entity_id":"104","attribute_set_id":"9","type_id":"simple","sku":"MH04-S-White","has_options":"0","required_options":"0","created_at":"2018-10-08 07:35:50","updated_at":"2018-10-08 07:35:50"},{"entity_id":"105","attribute_set_id":"9","type_id":"simple","sku":"MH04-S-Yellow","has_options":"0","required_options":"0","created_at":"2018-10-08 07:35:50","updated_at":"2018-10-08 07:35:50"},{"entity_id":"106","attribute_set_id":"9","type_id":"simple","sku":"MH04-M-Green","has_options":"0","required_options":"0","created_at":"2018-10-08 07:35:50","updated_at":"2018-10-08 07:35:50"},{"entity_id":"107","attribute_set_id":"9","type_id":"simple","sku":"MH04-M-White","has_options":"0","required_options":"0","created_at":"2018-10-08 07:35:50","updated_at":"2018-10-08 07:35:50"}]

I am getting collection using class as:

\Magento\Catalog\Model\ResourceModel\Product\CollectionFactory $productCollectionFactory

and

public function getProductCollection()
{
    $collection = $this->_productCollectionFactory->create();
    $collection->addAttributeToSelect('name')->addAttributeToSelect('sku');
    $page = $this->getRequest()->getParam('page');
    $collection->setPageSize(50)->setCurPage($page);
    return json_encode($collection->getData());

}

Best Answer

You should use an array:

$collection->addAttributeToSelect(['name','sku']);

$collection->addAttributeToSelect('name')->addAttributeToSelect('sku');

protected $_productCollection;

public function __construct(
...........
\Magento\Catalog\Model\ResourceModel\Product\CollectionFactory $productCollection,
...........
) {
    ...........
    $this->_productCollection = $productCollection;
    ...........
}

and

public function getProductCollection()
{
    $collection = $this->_productCollectionFactory->create();
    $collection->getCollection()->addAttributeToSelect(['name','sku']);
    $page = $this->getRequest()->getParam('page');
    $collection->setPageSize(50)->setCurPage($page);
    return json_encode($collection->getData());
}

Related Solutions

Collection – addAttributeToSelect Not Working with core/resource_iterator

Unfortunately the core/iterator resource model does not work well with EAV models, because it directly works with the query and does not use any of the collection specific features.

This is what usually happens when loading an EAV collection (I'll simplify a bit):

select basic data from the entity table (this is what $collection->getSelect() does
load the attributes from the value tables with an additional query and add this data to each loaded model

This all happens in the load() method (see Mage_Eav_Model_Entity_Collection_Abstract::_loadAttributes() if you want to see the implementation details)

Since the reason for using the resource iterator is usually that you don't want to load all data at once, you cannot use this feature in a reasonable way.

I tried to build a single query with joins instead, but soon ran into the problem that MySQL "only" allows 63 joins at a time. If you only need a few attributes, it might work for you, though.

Otherwise your best bet is to load and process the collection in chunks like this:

$ids = Mage::getModel('catalog/product')
    ->getCollection()
    ->getAllIds();

$page = 1;
do {
    $collection = Mage::getModel('catalog/product')
        ->getCollection()
        ->addIdFilter($ids)
        ->setPageSize(100)
        ->setPage($page);
    $results = $collection->load();
    // do stuff ...
    $page++;
} while ($results->count());

Magento – product->isSalable() false positive

it depends on what you want to do with the collection.
If you display it on frontend, you should add the status field to the collection.
You should also add a filter to the collection on the status.

->addAttributeToFilter('status', Mage_Catalog_Model_Product_Status::STATUS_ENABLED)

because you don't want users to see the disabled product. They will not be able to add them to the cart anyway.
If you have the flat catalog enabled, it should not be a problem, because only enabled products are added to the flat tables.
But add the filter anyway, just to be paranoid.

Best Answer

Related Solutions

Collection – addAttributeToSelect Not Working with core/resource_iterator

Magento – product->isSalable() false positive

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