mjoraid

DELETE 
  EntityMediaGallery 
FROM
  `catalog_product_entity_media_gallery_value_to_entity` ValueToEntity 
  INNER JOIN `catalog_product_entity_media_gallery_value` MediaGalleryValue 
    ON ValueToEntity.entity_id = MediaGalleryValue.entity_id 
    AND ValueToEntity.`value_id` = MediaGalleryValue.`value_id` 
    /* and MediaGalleryValue.`entity_id` = 320*/
  INNER JOIN `catalog_product_entity_media_gallery` EntityMediaGallery 
    ON ValueToEntity.`value_id` = EntityMediaGallery.`value_id`