magento 2 unable to get product Ids in foreach loop

Question

I am trying to get all product ids of multi-select attribute "filter_type" ids($optionData) are assigned.

But I am unable to get them as its only works first time. In second and other loop I am not getting any products. However its working fine when I pass id manually in place of (int)$optionValues. e.g. 441 etc.

   $optionData = array('435','436','437','438','441','439');
    $productIds = array();
    foreach ($optionData as $optionValues) {
         $productIds[] = $_productCollection->addAttributeToFilter(
                    array(
                        array('attribute' => "filter_type", 'finset' => (int)$optionValues)
                    )
                )->getAllIds();          

    }
    echo "<pre>"; print_r($productIds);

`

Answer 1

It will be because you are adding a new filter each iteraction rather than replacing the current filter. Instead you can either reset the where query if you only have the 1 filter parameter or you can create a copy of the query each iteraction.

To reset the where query

foreach ($optionData as $optionValues) {
     $_productCollection->getSelect()->reset(\Magento\Framework\DB\Select::WHERE);
     $productIds[] = $_productCollection->addAttributeToFilter(
         array(array('attribute' => "filter_type", 'finset' => (int)$optionValues))
     )->getAllIds();          
}

Or to create a copy

foreach ($optionData as $optionValues) {
     $_tmpProdCollection = clone $_productCollection;
     $productIds[] = $_tmpProdCollection->addAttributeToFilter(
         array(array('attribute' => "filter_type", 'finset' => (int)$optionValues))
     )->getAllIds();    
     unset($_tmpProdCollection);      
}

Answer 2

Can you please try below code which can be help to resolved it.

$optionData = array('435','436','437','438','441','439');
$productIds = array();
foreach ($optionData as $optionValues) {
     $productIds[$optionValues][] = $_productCollection->addAttributeToFilter(
                array(
                    array('attribute' => "filter_type", 'finset' => (int)$optionValues)
                )
            )->getAllIds();          

}
echo "<pre>"; print_r($productIds);

Thanks, Ketan T.