Magento 2: join custom table with product collection while sql query is running fine

Question

I trying to join custom table with product collection but I am not getting result. But printed SQL query is running fine

namespace Vendor\Module\Block\Product;
use Magento\Catalog\Api\CategoryRepositoryInterface;
use Magento\Catalog\Model\ProductFactory;
use Magento\Framework\View\Element\Template\Context;

class ListProduct extends \Magento\Catalog\Block\Product\ListProduct
{

protected function _getProductCollection(){


        if ($this->_productCollection === null) {
            $layer = $this->getLayer();
            /* @var $layer \Magento\Catalog\Model\Layer */
            if ($this->getShowRootCategory()) {
                $this->setCategoryId($this->_storeManager->getStore()->getRootCategoryId());
            }

            // if this is a product view page
            if ($this->_coreRegistry->registry('product')) {
                // get collection of categories this product is associated with
                $categories = $this->_coreRegistry->registry('product')
                    ->getCategoryCollection()->setPage(1, 1)
                    ->load();
                // if the product is associated with any category
                if ($categories->count()) {
                    // show products from this category
                    $this->setCategoryId(current($categories->getIterator()));
                }
            }

            $origCategory = null;
            if ($this->getCategoryId()) {
                try {
                    $category = $this->categoryRepository->get($this->getCategoryId());
                } catch (NoSuchEntityException $e) {
                    $category = null;
                }

                if ($category) {
                    $origCategory = $layer->getCurrentCategory();
                    $layer->setCurrentCategory($category);
                }
            }
            $this->_productCollection = $layer->getProductCollection();

            $this->prepareSortableFieldsByCategory($layer->getCurrentCategory());

            if ($origCategory) {
                $layer->setCurrentCategory($origCategory);
            }
        }

$collection = $this->_productCollectionFactory->create();
$collection->addAttributeToSelect('*');
$joinConditions = 'e.entity_id = s.product_id';
$collection->addAttributeToSelect('*');
$collection->getSelect()->join(
             ['s' => 'store_price'],
             $joinConditions,
             []
            )->columns("s.product_price")->where("s.store_id=1");


    //$this->_productCollection->printlogquery(true)    

    return $collection;

   }

     /**
     * Retrieve loaded category collection
     *
     * @return AbstractCollection
     */
    public function getLoadedProductCollection()
    {   
        return $this->_getProductCollection();
    }  

SQL Query //$this->_productCollection->printlogquery(true)

    SELECT 
    `e`.*, `cat_index`.`position` AS `cat_index_position`, 
    `stock_status_index`.`stock_status` AS `is_salable`, 
    `price_index`.`price`, `price_index`.`tax_class_id`, `price_index`.`final_price`, 
    IF(price_index.tier_price IS NOT NULL, 
    LEAST(price_index.min_price, price_index.tier_price), price_index.min_price) AS `minimal_price`, 
    `price_index`.`min_price`, `price_index`.`max_price`, `price_index`.`tier_price`, `s`.`product_price` 
FROM 
    `catalog_product_entity` AS `e` 
INNER JOIN 
    `catalog_category_product_index` AS `cat_index` 
ON 
    cat_index.product_id=e.entity_id AND cat_index.store_id=1 
    AND cat_index.visibility IN(2, 4) AND cat_index.category_id='2' 
    AND cat_index.is_parent=1 
LEFT JOIN 
    `cataloginventory_stock_status` AS `stock_status_index` 
ON 
    e.entity_id = stock_status_index.product_id AND stock_status_index.website_id = 0 AND stock_status_index.stock_id = 1 
INNER JOIN 
    `catalog_product_index_price` AS `price_index` 
ON 
    price_index.entity_id = e.entity_id AND price_index.website_id = '1' AND price_index.customer_group_id = 0 
INNER JOIN 
    `store_price` AS `s` ON e.entity_id = s.product_id WHERE (s.store_id = 1)   

Answer 1

I finallly found solution. Actually collection making alias for join table. You don't have to set alias

$joinConditions = 'e.entity_id = store_price.product_id';
$collection->addAttributeToSelect('*');
$collection->getSelect()->join(
             ['store_price'],
             $joinConditions,
             []
            )->columns("store_price.product_price")
              ->where("store_price.store_id=1");

Answer 2

Magento will be much more friendly if you stop using unnecessary rewrites and use Observers more often. For your problem you need to add:

Vendor/Module/etc/frontend/events.xml:

<config xmlns:xsi='http://www.w3.org/2001/XMLSchema-instance' xsi:noNamespaceSchemaLocation='urn:magento:framework:Event/etc/events.xsd'>
    <event name='catalog_block_product_list_collection'>
        <observer
            name='Vendor\Module\Observer\Catalog\Product\AddSmtToCollection'
            instance='Vendor\Module\Observer\Catalog\Product\AddSmtToCollection'
        />
    </event>
</config>

Vendor/Module/Observer/Catalog/Product/AddSmtToCollection.php

namespace Vendor\Module\Observer\Catalog\Product;

use Magento\Framework\Event\ObserverInterface;

class AddSmtToCollection implements ObserverInterface
{
    protected $logger;
    protected $customerSession;
    protected $helper;

    /**
     * @param \Psr\Log\LoggerInterface $logger
     * @param \Magedelight\Customerprice\Helper\Data $helper
     * @param \Magento\Customer\Model\Session $customerSession
     */
    public function __construct(
        \Psr\Log\LoggerInterface $logger
    ) {
        $this->logger = $logger;
    }

    /**
     * @param \Magento\Framework\Event\Observer $observer
     */
    public function execute(\Magento\Framework\Event\Observer $observer) {
        $ObjectManager = \Magento\Framework\App\ObjectManager::getInstance();

        $joinConditions = 'e.entity_id = store_price.product_id';
        $observer->getCollection()->getSelect()->join(
         ['store_price'],
         $joinConditions,
         []
        )->columns("store_price.product_price")
          ->where("store_price.store_id=1");

    }
}

Important note: You should be aware of joining custom tables, if you use flat table for products.

Answer 3

Suppose you want two custom attributes by raw query,

LEFT JOIN catalog_product_entity_varchar AS custom1 ON (custom1.entity_id = maintable.product_id) AND (custom1.attribute_id = '370')

LEFT JOIN catalog_product_entity_varchar AS custom2 ON (custom2.entity_id maintable.product_id) AND (custom2.attribute_id = '158')

Where as maintainable provides you the product id, and attribute_id are ids of custom attributes you want to fetch.

Answer 4

        $products->getSelect()->joinLeft(
            ['ot'=>$buySellTable],
            "ot.inv_id = e.entity_id",
            [
                'ot.sold_date','ot.listed_date','ot.purchase_price','ot.stock_number'
            ]
        )->where('ot.purchase_price <= ?', $priceToCheck);