When featured images are added the following records go into the WP DB:
wp_posts > 1 record
- post_type = “attachment”
- post_mime_type = “image/jpeg”
- post_parent = (ID of post it’s attached to)
wp_postmeta > 2 records
- _wp_attached_file = (relative path in /wp-content/uploads/, e.g. “2012/07/filename.jpg”)
- _wp_attachment_metadata = (really abstruse string containing a variety of size and other meta data)
CSV Importer might be able to handle this. It will be able to import it as a post though not sure if it can handle the mime type field (try column header “csv_post_mime_type”) – might not need it. As for the wp_postmeta key/value pairs, CSV Importer adds unfamiliar fields as records in the wp_postmeta table (with current post’s ID), so including a column with heading “_wp_attached_file” will work, I think. The biggest problem is probably _wp_attachment_metadata field… you might be able to generate this value if you start have the filename and image width/height. But to give you an idea, here’s a sample value from that field for an image added with default settings:
a:6:{s:5:”width”;s:3:”450“;s:6:”height”;s:3:”338“;s:14:”hwstring_small”;s:23:”height=’96’ width=’128′”;s:4:”file”;s:14:”2012/06/mm.jpg“;s:5:”sizes”;a:2:{s:9:”thumbnail”;a:3:{s:4:”file”;s:14:”mm-150×150.jpg”;s:5:”width”;s:3:”150″;s:6:”height”;s:3:”150″;}s:6:”medium”;a:3:{s:4:”file”;s:14:”mm-300×225.jpg”;s:5:”width”;s:3:”300″;s:6:”height”;s:3:”225″;}}s:10:”image_meta”;a:10:{s:8:”aperture”;s:1:”0″;s:6:”credit”;s:0:””;s:6:”camera”;s:0:””;s:7:”caption”;s:0:””;s:17:”created_timestamp”;s:1:”0″;s:9:”copyright”;s:0:””;s:12:”focal_length”;s:1:”0″;s:3:”iso”;s:1:”0″;s:13:”shutter_speed”;s:1:”0″;s:5:”title”;s:0:””;}}
(the parts in bold are specific to my image)
