DROP VIEW IF EXISTS total_admin_amout_view;
CREATE VIEW total_admin_amout_view (
 project_id,
 total_admin_amount
) as 
SELECT
    project_admin_offers.project_id
    , sum(project_admin_offers.price_per_article * po.volume ) as total_admin_amount
FROM
    project_admin_offers 
    INNER JOIN project_offers as po on po.project_id = project_admin_offers.project_id
GROUP BY project_admin_offers.project_id;