只需查找release\\u date\\u db即可完成此操作：

function plugin_name_get_posts() {
    global $wpdb;
$the_posts = $wpdb->get_results( "SELECT * FROM $wpdb->posts, $wpdb->postmeta WHERE $wpdb->posts.ID = $wpdb->postmeta.post_id AND meta_key = \'release_date_db\' AND meta_value >= 20120000 AND meta_value <= 20121231 ORDER BY meta_value ASC;", ARRAY_A );
 }