OCP-047 delete

96. View the Exhibit and examine the structure of ORDERS and ORDER_ITEMS
tables.ORDER_ID is the primary key in the ORDERS table. It is also the foreign
key in the ORDER_ITEMS table where in it is created with the ON DELETE CASCADE
option. Which DELETE statement would execute successfully?
A. DELETE order_id FROM orders WHERE order_total < 1000;
B. DELETE orders WHERE order_total < 1000;
C. DELETE FROM orders WHERE (SELECT order_id FROM order_items);

D.DELETE orders o, order_items I WHERE o.order_id = i.order_id;

Answer: B

常用的delete 语法为：

DELETE FROM table_Name where coln_name =???

FROM 关键字其实是可选的； delete table .....也可以