更新表、删除表的条件可以引用多个表。。 update例子如下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)DELETE例子如下 DELETE FROM titleauthor WHERE title_id IN (SELECT title_id FROM titles WHERE title LIKE '%computers%')
update例子如下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)DELETE例子如下
DELETE FROM titleauthor
WHERE title_id IN
(SELECT title_id
FROM titles
WHERE title LIKE '%computers%')