QUERY:
SELECT
materials_prices.id,
IF(name_dk != '', name_dk, name_et) AS name,
materials_prices.thickness,
materials_prices.price_dk,
CONCAT('https://www.granimar.ee/files/products/medium/medium_', product_files.filename) AS file_url,
CONCAT('/data01/virt60350/domeenid/www.granimar.ee/htdocs/files/products/medium/medium_', product_files.filename) AS file_path
FROM mdl_price_calculator_materials AS materials_prices
JOIN mdl_shop_product_files AS product_files
ON materials_prices.id = product_files.fk_product_id
JOIN mdl_shop_products AS products
ON materials_prices.id = products.id
WHERE materials_prices.thickness = 12
AND product_files.type = 'image'