Craft\Formerly_SubmissionElementType::modifyElementsQuery PHP Method

    public function modifyElementsQuery(DbCommand $query, ElementCriteriaModel $criteria)
    {
        $query->addSelect('submissions.formId')->join('formerly_submissions submissions', 'submissions.id = elements.id');
        if ($criteria->formId) {
            $query->andWhere(DbHelper::parseParam('submissions.formId', $criteria->formId, $query->params));
        }
        if ($criteria->form) {
            $query->join('formerly_forms forms', 'forms.id = submissions.formId');
            $query->andWhere(DbHelper::parseParam('formerly_forms.handle', $criteria->form, $query->params));
        }
    }