post缩略图存储在{$wpdb->prefix}_postmeta 带键的表格_thumbnail_id.

类似这样：

SELECT * from {$wpdb->prefix}_posts 
WHERE ID in (
   SELECT meta_value FROM {$wpdb->prefix}_postmeta 
   WHERE meta_key = \'_thumbnail_id\'
   AND post_id = \':ID\'
);

这将返回与图像本身关联的帖子post_title 将是用户与图像上的title属性关联的任何内容guid 将是完整大小的图像URL。

如果你想要不同的尺寸，你必须查一下_wp_attachment_metadata Posteta值，该值将包含具有所有不同大小的序列化数组。

使用WordPress的api要容易得多：

<?php
if(has_post_thumbnail($some_post_id))
{
   $img = wp_get_attachment_img_src(get_post_thumbnail_id($some_post_id), \'the_image_size\');
   // returns an array, the first item is the image URL
   echo $img[0];
}

该帖子的特色图片是该帖子的常规旧附件。因此，与任何其他图像附件一样，您需要查询wp_posts 职位类型表attachment. 诀窍是首先获取需要获取的附件ID。

这包含在给定帖子的元信息中，特别是_thumbnail_id 元。

因此，您需要一个查询：

检索键标记的值_thumbnail_id 在wp_postmeta 基于给定帖子ID的表。从wp_posts 基于步骤1中检索到的ID的表根据步骤2中检索到的信息生成一个附件永久链接。实际上，您需要做大量的工作来重新设计轮子。。。

以下是我用来检索帖子数据、特色图片URL和特色图片详细信息（如尺寸）的内容：

SELECT p.*, ( SELECT guid FROM wp_posts WHERE id = m.meta_value ) AS imgurl,  (SELECT meta_value FROM wp_postmeta pm WHERE meta_key=\'_wp_attachment_metadata\' AND pm.post_id=m.meta_value ) AS imgdetails
FROM wp_posts p
LEFT JOIN  wp_postmeta m ON(p.id = m.post_id AND m.meta_key =  \'_thumbnail_id\' )
WHERE p.post_type =  \'post\'
AND p.post_status =  \'publish\' AND p.id=@postId;

使用下一个查询检索所有帖子的特色图片：

SELECT result.post_parent, result.guid AS featuredImage
FROM wp_posts AS p 
INNER JOIN wp_postmeta AS pm ON p.ID=pm.post_id
INNER JOIN wp_posts as result ON pm.meta_value = result.ID
WHERE pm.meta_key = \'_thumbnail_id\' AND p.post_type=\'post\' AND 
p.post_status = \'publish\'

最好的SQL解决方案，

从wp\\U post中搜索ID

SELECT * FROM wp_posts WHERE post_status=\'publish\'

找到元内容

SELECT * FROM wp_postmeta WHERE meta_key=\'_thumbnail_id\' AND post_id=MyID

SELECT * FROM wp_postmeta WHERE meta_key=\'_wp_attached_file\' AND post_id=MyID

$query = mysql_query("SELECT  * FROM wp_posts WHERE post_status=\'publish\' ORDER  BY id DESC LIMIT 6") or die(mysql_error());
    $json=\'{ "Blog" : [ \';
    while($row =mysql_fetch_array($query)){

        $queryMeta=mysql_query("SELECT * FROM wp_postmeta WHERE meta_key=\'_thumbnail_id\' AND post_id=$row[ID]") or die(mysql_error());

        $f=mysql_fetch_array($queryMeta);

        $value=$f[meta_value];

        $queryMeta2=mysql_query("SELECT * FROM wp_postmeta WHERE meta_key=\'_wp_attached_file\' AND post_id=$value") or die(mysql_error());

        $f2=mysql_fetch_array($queryMeta2);

        $value=$f2[meta_value];

        $json.=\'{"id" : "\'.$row[ID].\'" ,  "date" : "\'.$row[post_date].\'", "title" :"\'.$row[post_title].\'", "link" : "\'.$row[guid].\'" ,  "image" :"https://dartesanos.com/blog/wp-content/uploads/\'.$value.\'" },\';

    }
    $json=substr($json,0,-1);

    echo $json ."]}";