The Hemlock in the U.S. will be saved from HWA soon.A．YB．NC．NG

A.The DESCRIBE DEPT statement displays the structure of the DEPT table.

B.The ROLLBACK statement frees the storage space occupied by the DEPT table.

C.The DESCRIBE DEPT statement returns an error ORA-04043: object DEPT does not exist.

D.The DESCRIBE DEPT statement displays the structure of the DEPT table only if there is a COMMIT statement introduced before the ROLLBACK statement.

A. CREATE ROLE manager; GRANT create table, create view TO manager; GRANT manager TO BLACK, CLARK;

B. CREATE ROLE manager; GRANT create table, create voew TO manager; GRANT manager ROLE TO BLACK, CLARK;

C. GRANT manager ROLE TO BLACK, CLARK; GRANT create table, create voew TO BLACK CLARK; ***MISSING***

A. CREATE ROLE manager; GRANT create table, create view TO manager; GRANT manager TO BLACK, CLARK;

B. CREATE ROLE manager; GRANT create table, create voew TO manager; GRANT manager ROLE TO BLACK, CLARK;

C. GRANT manager ROLE TO BLACK, CLARK; GRANT create table, create voew TO BLACK CLARK; ***MISSING***

A. The DESCRIBE DEPT statement displays the structure of the DEPT table.

B. The ROLLBACK statement frees the storage space occupies by the DEPT table.

C. The DESCRIBE DEPT statement returns an error ORA-04043: object DEPT does not exist.

D. The DESCRIBE DEPT statement displays the structure of the DEPT table only if there is a COMMIT statement introduced before the ROLLBACK statement.

Scott issues the SQL statements:CREATE TABLE dept(deptno NUMBER(2),dname VARCHAR2(14),loc VARCHAR2(13)};GRANT SELECTON DEPTT0 SUE;If Sue needs to select from Scott‘s DEPT table, which command should she use？（）

A.SELECT*FROMDEPT；

B.SELECT*FROMSCOTT.DEPT；

C.SELECT*FROMDBASCOTTDEPT；

D.SELECT*FROMALL_USERSWHEREUSER_NAME=‘；SCOTT‘；ANDTABLENAME=‘；DEPT‘；；

A. You cannot roll back this statement.

B. All pending transactions are committed.

C. All views based on the DEPT table are deleted.

D. All indexes based on the DEPT table are dropped.

E. All data in the table is deleted, and the table structure is also deleted.

F. All data in the table is deleted, but the structure of the table is retained.

G. All synonyms based on the DEPT table are deleted.

Examine the SQL statements that creates ORDERS table: CREATE TABLE orders(SER_NO NUMBER UNIQUE,ORDER_ID NUMBER,ORDER_DATE DATE NOT NULLSTATUS VARCHARD2(10)CHECK (status IN (‘CREDIT‘,‘CASH‘)),PROD_ID_NUMBERREFERENCES 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

Examine the following command:CREATE TABLE (prod_id number(4),Prod_name varchar2 (20),Category_id number(30),Quantity_on_hand number (3) INVISIBLE);Which three statements are true about using an invisible column in the PRODUCTS table？（）

A. The %ROWTYPE attribute declarations in PL/SQL to access a row will not display the invisible column in the output.

B. The DESCRIBE commands in SQL *Plus will not display the invisible column in the output.

C. Referential integrity constraint cannot be set on the invisible column.

D. The invisible column cannot be made visible and can only be marked as unused.

E. A primary key constraint can be added on the invisible column.

A．CREATE TABLE

B． CREATE VIEW

C． CREATE INDEX

D． ALTER TABLE