至少有two (2) ways 要实现这一点：

你可以query the second database 这将要求您在两个位置维护数据库凭据，或者至少在包含文件中维护数据库凭据，或者

你可以create a simple JSON feed 对于你的照片博客，使用主博客上的提要并将其缓存一段时间。当缓存过期时，这将导致页面加载稍有延迟，但由于两者都在同一台机器上，因此不应成为问题。

请告诉我您喜欢哪一种，以及我是否会更新答案，以便您如何更新。

更新要连接到另一个数据库，您可以在此处阅读有关它的更多信息：

• Using wpdb to connect to a separate database

这是我为您拼凑的一个函数，名为show_thumbnails_2nd_db() 可以复制到主题的functions.php 文件：

function show_thumbnails_2nd_db() {
  global $wpdb;
  global $table_prefix;
  $save_wpdb = $wpdb;
  $save_prefix = $table_prefix;
  include_once(ABSPATH . \'/photos/database-credentials.php\');
  extract($database_credentials);
  $wpdb = new wpdb($DB_USER, $DB_PASSWORD, $DB_NAME, $DB_HOST);
  wp_set_wpdb_vars();

  // This is the code for featured images  
  $sql = <<<SQL
SELECT DISTINCT CONCAT(\'<img src="\',attachment.guid,\'"/>\') AS url
FROM 
  {$wpdb->posts} attachment
  INNER JOIN {$wpdb->postmeta} ON attachment.ID={$wpdb->postmeta}.meta_value AND {$wpdb->postmeta}.meta_key=\'_thumbnail_id\'
  INNER JOIN {$wpdb->posts} ON {$wpdb->posts}.ID={$wpdb->postmeta}.post_id
WHERE {$wpdb->posts}.post_status=\'publish\'
  AND attachment.post_type=\'attachment\'
ORDER BY attachment.ID DESC
LIMIT 10
SQL;
  $post_urls = $wpdb->get_col($sql);
  if (is_array($post_urls))
    echo implode("\\n",$post_urls);

// This is the code for post thumbnails  
//   $sql = <<<SQL
// SELECT DISTINCT {$wpdb->posts}.ID
// FROM {$wpdb->posts}
// INNER JOIN {$wpdb->posts} attachment
//    ON {$wpdb->posts}.ID=attachment.post_parent
// WHERE {$wpdb->posts}.post_status=\'publish\'
//   AND attachment.post_type=\'attachment\'
// ORDER BY attachment.ID
// LIMIT 10
// SQL;
//   $post_ids = $wpdb->get_col($sql);
//   foreach($post_ids as $post_id) {
//     $thumbnail = get_the_post_thumbnail($post_id);
//     if ($thumbnail) {
//       echo $thumbnail;
//     }
//   }
  $table_prefix = $save_prefix;
  $wpdb = $save_wpdb;
}

Note: 以上假设您已创建database-credentials.php 在照片博客的根目录中，应该是这样的：

<?php    
$database_credentials = array(
  \'DB_NAME\' =>  \'your_database\',
  \'DB_USER\' =>  \'your_db_user\',
  \'DB_PASSWORD\' =>  \'your db password\',
  \'DB_HOST\' =>  \'localhost\',
  \'table_prefix\' => \'your_photos_db_prefix_\',
);

那么inside the /wp-config.php for your photos blog 您将替换如下代码部分：

// ** MySQL settings - You can get this info from your web host ** //
/** The name of the database for WordPress */
define(\'DB_NAME\', \'your_database\');

/** MySQL database username */
define(\'DB_USER\', \'your_db_user\');

/** MySQL database password */
define(\'DB_PASSWORD\', \'your db password\');

/** MySQL hostname */
define(\'DB_HOST\', \'localhost\');

还有这个：

$table_prefix  = \'wp_\';

使用此选项：

include_once(ABSPATH . \'/database-credentials.php\');

// ** MySQL settings - You can get this info from your web host ** //
/** The name of the database for WordPress */
define(\'DB_NAME\', $database_credentials[\'DB_NAME\']);

/** MySQL database username */
define(\'DB_USER\', $database_credentials[\'DB_USER\']);

/** MySQL database password */
define(\'DB_PASSWORD\', $database_credentials[\'DB_PASSWORD\']);

/** MySQL hostname */
define(\'DB_HOST\', $database_credentials[\'DB_HOST\']);

$table_prefix  = $database_credentials[\'table_prefix\'];

如果你需要更多的解释，请在评论中提问。