UPDATE titles
SET ytd_sales = titles.ytd_sales || sales.qty
FROM titles, sales
WHERE titles.title_id = sales.title_id
AND sales.ord_date = (SELECT MAX(sales.ord_date) FROM sales)
SET ytd_sales = titles.ytd_sales || sales.qty
FROM titles, sales
WHERE titles.title_id = sales.title_id
AND sales.ord_date = (SELECT MAX(sales.ord_date) FROM sales)
SET ytd_sales = titles.ytd_sales + (select sales.qty
FROM sales
WHERE titles.title_id = sales.title_id
AND sales.ord_date = (SELECT MAX(sales.ord_date) FROM sales));
SET ytd_sales = titles.ytd_sales + (select sales.qty
FROM sales
WHERE titles.title_id = sales.title_id
AND sales.ord_date = (SELECT MAX(sales.ord_date) FROM sales));