多项选择题 Evaluate the following statements：   CREATE TABLE purchase_orders （po_id NUMBER（4），  po_date TIMESTAMP， supplier_id NUMBER（6）， po_total NUMBER（8，2），  CONSTRAINT order_pk PRIMARY KEY（po_id）） PARTITION BY RANGE（po_date）  （PARTITION Q1 VALUES LESS THAN （TO_DATE（？1-apr-2007？d-mon-yyyy？）， PARTITION Q2 VALUES LESS THAN  （TO_DATE（？1-jul-2007？d-mon-yyyy？），  PARTITION Q3 VALUES LESS THAN（TO_DATE（？1-oct - 2007？d-mon-yyyy？）， PARTITION Q4 VALUES LESS THAN （TO_DATE（？1-jan-2008？d-mon-yyyy？））；  CREATE TABLE purchase_order_items （po_id NUMBER（4） NOT NULL， product_id NUMBER（6） NOT NULL， unit_price NUMBER（8，2）， quantity NUMBER（8）， CONSTRAINT po_items_fk FOREIGN KEY  （po_id） REFERENCES purchase_orders（po_id）） PARTITION BY REFERENCE（po_items_fk）；   What are the two consequences of the above statements？（）

单项选择题 To accomplish user-managed backup for the USERS tablespace, you issued the following command to put the database in backup mode: SQL> ALTER TABLESPACE users BEGIN BACKUP; While copying the file to the backup destination a power outage caused the instance to terminate abnormally. Which statement is true about the next database startup and the USERS tablespace?（）

单项选择题 View the Exhibit to examine the parameter values. You are planning to set the value for the MEMORY_TARGET parameter of your database instance. What value would you recommend?（）