Model/Sales/CouponGridFilterer.php
public function filterByGeneratedByDotmailer($collection, $column)
    {
        $field = $column->getFilterIndex() ? $column->getFilterIndex()
            : $column->getIndex();
        $value = $column->getFilter()->getValue();
        if ($value == 'null') {
            $collection->addFieldToFilter($field, ['null' => true]);
        } else {
            $collection->addFieldToFilter($field, ['notnull' => true]);
        }
    }
public function filterByGeneratedByDotmailer($collection, $column)
    {
        $field = $column->getFilterIndex() ? $column->getFilterIndex()
            : $column->getIndex();
        $value = $column->getFilter()->getValue();
        if ($value == 'null') {
            $collection->addFieldToFilter($field, ['null' => true]);
        } else {
            $collection->addFieldToFilter($field, ['notnull' => true]);
        }
    }
public function filterByGeneratedByDotmailer ( $ collection , $ column ) { $ field = $ column -> getFilterIndex ( ) ? $ column -> getFilterIndex ( ) : $ column -> getIndex ( ) ; $ value = $ column -> getFilter ( ) -> getValue ( ) ; if ( $ value == 'null' ) { $ collection -> addFieldToFilter ( $ field , [ 'null' => true ] ) ; } else { $ collection -> addFieldToFilter ( $ field , [ 'notnull' => true ] ) ; } }
Callback action for cart price rule coupon grid.

@param AbstractCollection $collection
@param Column $column
@return void
Callback action for cart price rule coupon grid .