多选题Examine the SQL statements that creates ORDERS table: For which columns would an index be automatically created when you execute the above SQL statement? （）ASER_NOBORDER_IDCSTATUSDPROD_IDEORD_TOTALFComposite index on ORDER_ID and ORDER_DATE

第1题：

Examine the following output： SQL> SELECT index_name，status FROM dba_indexes WHERE status=’UNUSABLE’； INDEX_NAME STATUS------------------------------ ----------- EIND UNUSABLE Which two statements about the above index are true（）

• A、It is ignored by the query optimizer.
• B、It is not used while the index is being rebuilt.
• C、The index cannot be rebuilt， and has to be re-created.
• D、The index is automatically rebuilt when used the next time

第2题：

Examine the SQL statement that creates ORDERS table: CREATE TABLE orders (SER_NO NUMBER UNIQUE, ORDER_ID NUMBER, ORDER_DATE DATE NOT NULL, STATUS VARCHAR2(10) CHECK (status IN ('CREDIT', 'CASH')), PROD_ID NUMBER REFERENCES PRODUCTS(PRODUCT_ID), ORD_TOTAL NUMBER, PRIMARY KEY (order_id, order_date)); For which columns would an index be automatically created when you execute the above SQL statement? （）

• A、SER_NO
• B、ORDER_ID
• C、STATUS
• D、PROD_ID
• E、ORD_TOTAL
• F、composite index on ORDER_ID and ORDER_DATE

第3题：

第4题：

On your Oracle Database, you issue the following commands to create indexes: SQL > CREATE INDEX oe.ord_customer_ix1 ON oe.orders (customer_id, sales_rep_id) INVISIBLE; SQL> CREATE BITMAP INDEX oe.ord_customer_ix2 ON oe.orders (customer_id, sales_rep_id); Which two statements are true?（）

• A、Only the ORD_CUSTOMER_IX1 index created.
• B、Both the indexes are updated when a row is inserted, updated, or deleted in the ORDERS table.
• C、Both the indexes are created: however, only ORD_CUSTOMERS_IX1 is used by the optimizer for queries on the ORDERS table.
• D、The ORD_CUSTOMER_IX1 index is not used by the optimizer even when the OPTIMIZER_USE_INVISIBLE_INDEXES parameters is set to true.
• E、Both the indexes are created and used by the optimizer for queries on the ORDERS table.
• F、Both the indexes are created: however, only ORD_CUSTOMERS_IX2 is used by the optimizer for queries on the ORDERS table.

第5题：

Examine the SQL statements that creates ORDERS table: CREATE TABLE orders (SER_NO NUMBER UNIQUE, ORDER_ID NUMBER, ORDER_DATE DATE NOT NULL STATUS VARCHARD2(10) CHECK (status IN ('CREDIT','CASH')), PROD_ID_NUMBER REFERENCES PRODUCTS(PRODUCT_ID), ORD_TOTAL NUMBER, PRIMARY KEY (order id, order date)); For which columns would an index be automatically created when you execute the aboveSQL statement? （）

• A、SER_NO
• B、ORDER_ID
• C、STATUS
• D、PROD_ID
• E、ORD_TOTAL
• F、Composite index on ORDER_ID and ORDER_DATE

第6题：

Evaluate the CREATE TABLE statement：   CREATE TABLE products   （product_id NUMBER （6）  CONSTRAINT prod_id_pk PRIMARY KEY，  product_name VARCHAR2 （15））；   Which statement is true regarding the PROD_ID_PK constraint？（）

• A、 It would be created only if a unique index is manually created first.
• B、 It would be created and would use an automatically created unique index.
• C、 It would be created and would use an automatically created nonunique index.
• D、 It would be created and remains in a disabled state because no index is specified in the command.

第7题：

Examine the command that is used to create a table：  SQL> CREATE TABLE orders（oid NUMBER（6） PRIMARY KEY， odate DATE， ccode NUMBER（6）， oamt NUMBER（10，2）） TABLESPACE users；  Which two statements are true about the effect of the above command） （）

• A、A CHECK constraint is created on the OID column.
• B、A NOT NULL constraint is created on the OID column.
• C、The ORDERS table is the only object created in the USERS tablespace.
• D、The ORDERS table and a unique index are created in the USERS tablespace.
• E、The ORDERS table is created in the USERS tablespace and a unique index is created on the OIDcolumn in the SYSTEM tablespace.

第8题：

第9题：

You created the ORDERS table in your database by using the following code：   SQL> CREATE TABLE ORDERS （ORDER_DATE TIMESTAMP（0） WITH TIME ZONE）；   Then， you inserted data in the ORDERS table and saved it by issuing the following statements：SQL> INSERT INTO ORDERS VALUES（’18-AUG-00 10：26：44 PM America/New_York’）；   SQL> INSERT INTO ORDERS VALUES（’23-AUG-02 12：46：34 PM America/New_York’）；   SQL> COMMIT；   Next， you issued the following statement to change the time zone for the database：   SQL> ALTER DATABASE SET TIME_ZONE=’Europe/London’；   What will be the result of executing the above statement？（）  

• A、 The statement will fail.
• B、 The statement will be executed successfully， and the new time zone will be set for the database.
• C、 The statement will be executed successfully， but the new time zone will be set for the current session.
• D、The statement will be executed successfully， but the new time zone will neither be set for the database nor for a specific session.

第10题：

Examine the following statement that is used to modify the constraint on the SALES table： SQL> ALTER TABLE SALES MODIFY CONSTRAINT pk DISABLE VALIDATE； Which three statements are true regarding the above command（）

• A、The constraint remains valid.
• B、The index on the constraint is dropped.
• C、It allows the loading of data into the table using SQL*Loader.
• D、New data conforms to the constraint， but existing data is not checked
• E、It allows the data manipulation on the table using INSERT/UPDATE/DELETE SQL statements.