DROP VIEW IF EXISTS prices_categories_project_list_view;
CREATE VIEW prices_categories_project_list_view (
 project_id,
 total_volumes,
 total_prices
) as
SELECT
    `project_id`,
    SUM(volume) AS `total_volumes`,
    SUM(price) AS `total_prices`
FROM
    `project_categories`
GROUP BY
    `project_id`;