how to add parent filter in Magento2 product collection?

Question

How to load new product collection in Magento 2 something like

$collection->addAttributeToFilter('parent_id', null);

I want all simple product which is not associate with configurable which mean it has no parent.

Or any other approach ?

Answer 1

I have added following join to the product collection query

 $collection->getSelect()->joinLeft(
        'catalog_product_super_link',
        'e.entity_id = catalog_product_super_link.product_id'
    )->where ("catalog_product_super_link.product_id IS NULL");

and got the desired collection.