1z0-071 Oracle Database 12c SQL 第13题 ON DELETE CASCADE选项

Q13. 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 wherein 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;

Correct Answer: B