select 
`article_id`,
concat_ws("-", `ph`.`photo_id`, coalesce(`ph`.`image_file`, 'noimage.png')) as `images`,
`art`.`article`, 
coalesce(`art`.`price_discounted`, ceil( `art`.`price_retail`*`art`.`retail_discount`/10)*10) as `price_discounted`,
coalesce(`ph`.`sort_order`, 1) as `cso`
from `article` as `art`
left join `photo` as `ph`
using(`article_id`)
group by `article_id`, `ph`.`sort_order`
having `article_id` in (47,74,75) 
and `cso`=1;

select 
`art`.`article_id`, 
`art`.`article`, 
coalesce(`art`.`price_discounted`, ceil( `art`.`price_retail`*`art`.`retail_discount`/10)*10) as `price_discounted`
from `article` as `art`
where `art`.`article_id` in (47,74,75);

select 
`ph`.`article_id`, 
concat_ws("-", `ph`.`photo_id`, coalesce(`ph`.`image_file`, 'noimage.png')) as `images`
from `photo` as `ph`
where `ph`.`article_id` in (47,74,75) 
and `ph`.`sort_order`=1;