Importing featured images from posts

Featured images are not referenced by URL, but by attachment ID. A post’s featured image export entry looks like this:

<wp:postmeta>
		<wp:meta_key><![CDATA[_thumbnail_id]]></wp:meta_key>
		<wp:meta_value><![CDATA[1234]]></wp:meta_value>
		</wp:postmeta>

Where 1234 is the attachment ID for the image. If the export file has this ID anywhere within whatever XML element (but not like the example), perhaps you can do some search/replace magic on the file to cause an entry like above to occur with the right ID. Before doing so, do a spot check to ensure the image attachment posts still have the correct post_id values. In other words, does the thumbnail ID relate to the right attachment post’s image?

If the correct ID is nowhere to be found in the export file, you could go to the source DB and via phpMyAdmin, export whatever records under which the featured image is saved. Unless the data is under meta_key _thumbnail_id, you’ll likely need some custom code to translate the data into proper WP featured image schema.

Thanks for answering me so quickly!

This is the complete excerpt of the export xml for one post:

[{"post_id":8825,"meta_key":"_edit_lock","meta_value":"1639261024:76"},{"post_id":8825,"meta_key":"_edit_last","meta_value":"4"},{"post_id":8825,"meta_key":"slide_template","meta_value":"default"},{"post_id":8825,"meta_key":"rttheme_header_background_image","meta_value":""},{"post_id":8825,"meta_key":"rttheme_header_text","meta_value":""},{"post_id":8825,"meta_key":"rttheme_background_image_url","meta_value":""},{"post_id":8825,"meta_key":"rttheme_background_color","meta_value":""},{"post_id":8825,"meta_key":"rttheme_background_overlay_image_url","meta_value":""},{"post_id":8825,"meta_key":"rttheme_enable_background_overlay","meta_value":"on"},{"post_id":8825,"meta_key":"rttheme_rt_hidden","meta_value":"saved"},{"post_id":8825,"meta_key":"post_format","meta_value":""},{"post_id":8825,"meta_key":"rtthemefeatured_image_position","meta_value":""},{"post_id":8825,"meta_key":"rtthemeblog_image_resize","meta_value":"on"},{"post_id":8825,"meta_key":"rtthemeblog_image_width","meta_value":"0"},{"post_id":8825,"meta_key":"rtthemeblog_image_height","meta_value":"0"},{"post_id":8825,"meta_key":"rtthemeblog_image_crop","meta_value":"on"},{"post_id":8825,"meta_key":"rtthemefeatured_image_in_single_post_page","meta_value":"on"},{"post_id":8825,"meta_key":"rtthemeis_old_post","meta_value":"1"},{"post_id":8825,"meta_key":"rttheme_post_video_m4v","meta_value":""},{"post_id":8825,"meta_key":"rttheme_post_video_ogv","meta_value":""},{"post_id":8825,"meta_key":"rtthemevideo_url","meta_value":""},{"post_id":8825,"meta_key":"rttheme_post_audio_mp3","meta_value":""},{"post_id":8825,"meta_key":"rttheme_post_audio_oga","meta_value":""},{"post_id":8825,"meta_key":"rttheme_featured_image_usage","meta_value":"slider"},{"post_id":8825,"meta_key":"rttheme_display_gallery_images","meta_value":"same"},{"post_id":8825,"meta_key":"rtthemegallery_images_crop","meta_value":"on"},{"post_id":8825,"meta_key":"rtthemegallery_images_height","meta_value":"300"},{"post_id":8825,"meta_key":"rtthemephoto_gallery_images_width","meta_value":"160"},{"post_id":8825,"meta_key":"rtthemephoto_gallery_images_height","meta_value":"160"},{"post_id":8825,"meta_key":"rtthemepost_format_link","meta_value":""},{"post_id":8825,"meta_key":"rtthemecustom_sidebar_position","meta_value":""},{"post_id":8825,"meta_key":"rtthemert_gallery_images","meta_value":"a:1:{i:0;s:70:\"https:\/\/mysite.com\/wp-content\/uploads\/2021\/11\/IMG.jpg\";}"},{"post_id":8825,"meta_key":"rtthemert_gallery_image_titles","meta_value":"a:1:{i:0;s:0:\"\";}"},{"post_id":8825,"meta_key":"rtthemert_gallery_image_descs","meta_value":"a:1:{i:0;s:0:\"\";}"}]

I don′t see any reference to the id of the media. Googling around I found how to get the ID using the URL by a query:

select * from wp_posts WHERE post_type='attachment' and post_status='inherit' and guid like '%https:\/\/mysite.com\/wp-content\/uploads\/2021\/11
\/IMG.jpg%';

However I don′t know how I could insert those IDs into the export file. Maybe WP-CLI and the export function can be of any use?

• This reply was modified 3 years, 3 months ago by bcworkz. Reason: code format fixed

For that query to work you would need to know every post’s featured image URL. Compiling all of that for 258 posts sounds extremely time consuming.

Ideally we’d want to determine how the theme actually does relate the featured image to each post. Then we could export relevant data and develop a custom script that parses through the data file and assigns featured images the way WP expects them to be assigned. While it’s feasible to inject added data into a WP export file, it’s likely easier to manage featured image assignment after the initial import.

Either the theme uses some method independent of postmeta, like a custom table; or the relevant postmeta hadn’t been included in the export file even though it may be there. It may take some rooting around in phpMyAdmin app to learn how the theme is doing this. Or try asking for guidance through the theme’s dedicated support channel.