我有一个查询，可以防止没有各种条件的帖子出现，其中之一就是必须有一个特色图片。然而，不管怎样，粘性帖子似乎最终会出现在查询中。我怎样才能做到这一点？

    $args = array(
            \'posts_per_page\' => $articles_no,
            \'meta_key\' => \'_thumbnail_id\',
            \'post__not_in\' => $a_empty_titles,
            // remove post formats as per theme options ( using $hide from above )
            \'tax_query\' => array(
                    array(
                        \'taxonomy\' => \'post_format\',
                        \'field\' => \'slug\',
                        \'operator\' => \'NOT IN\',
                        \'terms\' => $hide
                    )
                )
            );
        $fp_query = new WP_Query( $args ); ?>
            <ul class="thumbnails">
                <?php 
                $thumbnail_span = "span4";
                if( $fp_query->have_posts() ) : while( $fp_query->have_posts() ) : $fp_query->the_post(); ?>

                ... Typical Formatting Follows ...
                ... Posts without featured images should have been excluded but "sticky" posts seem to persist