What might be the reason? Or where should I start looking for a fix in the Magento import process?
What happens? When we import product (or only images to an existing product) to CSV through import the base image is and stays as a placeholder image. Thumbnail image in catalog gets updated but on product page no image other than placeholder is visible. I have double-checked that the images are in the correct pub/media/import folder with proper rights. Magento version to this behavior is not exact, due this problem was current on previous versions also. After the import, the admin UI just says import successful and I haven't found any clues from log either. Everything seems smooth as ...
If we add the images from the admin backend UI it updates it correctly.
I tracked the behavior down to the database catalog_product_entity_media_gallery table has entries of all the images imported through CSV. catalog_product_entity_media_gallery_value_to_entity has no record of the product nor the image imported through CSV. catalog_product_entity_media_gallery_value doesn't have any records with the entity id.
If I export the products from the store as CSV. The export file has correct image file names on and labels all columns. The ones we just imported. But they are not visible in media_gallery_value table? I assume export reads the data from catalog_product_entity_varchar so this doesn't reflect that fact that the info is really missing from where it should be used.
I'm puzzled. Obviously, I have something misplaced somewhere. But from where to start? I want my product images ;)