Yii2 in the batchInsert command, for some reason, one empty record is created?

Question

Yii

foreach($_POST[PostData] as $key => $value){
                $str = strpos($key, "_");
                $key = substr($key, 0, $str);

                $postData->data_type = $key;
                $postData->post_data = $value;
                $postData->post_id;

                $rows[] = [
                    'post_id' => $postData->post_id,
                    'data_type' => $postData->data_type,
                    'post_data' => $postData->post_data
                ];
            }

            array_shift($rows);

            Yii::$app->db->createCommand()->batchInsert($postData::tableName(), ['post_id', 'data_type', 'post_data'], $rows)->execute();