Which statement describes the ROWID data type?（）

单项选择题You need to produce a report for mailing labels for all customers. The mailing label must have only the customer name and address. The CUSTOMERS table has these columns: Which SELECT statement accomplishes this task?（）

A. SELECT*   FROM customers;
B. SELECT name, address   FROM customers;
C. SELECT id, name, address, phone   FROM customers;
D. SELECT cust_name, cust_address   FROM customers;
E. SELECT cust_id, cust_name, cust_address, cust_phone   FROM customers;

单项选择题The STUDENT_GRADES table has these columns STUDENT_ID NUMBER(12) SEMESTER_END DATE GPA NUMBER(4,3) Which statement finds students who have a grade point average (GPA) greater than 3.0 for the calendar year 2001?（）

A. SELECT student_id, gpa FROM student_grades WHERE semester_end BETWEEN '01-JAN-2001' AND '31-DEC-2001' OR gpa > 3.;
B. SELECT student_id, gpa FROM student_grades WHERE semester_end BETWEEN '01-JAN-2001' AND '31-DEC-2001' AND gpa gt 3.0;
C. SELECT student_id, gpa FROM student_grades WHERE semester_end BETWEEN '01-JAN-2001' AND '31-DEC-2001' AND gpa > 3.0;
D. SELECT student_id, gpa FROM student_grades WHERE semester_end > '01-JAN-2001' OR semester_end < '31-DEC-2001' AND gpa >=s 3.0;

多项选择题Which two statements complete a transaction?（）

A. DELETE employees;
B. DESCRIBE employees;
C. ROLLBACK TO SAVEPOINT C;
D. GRANT SELECT ON employees TO SCOTT;
E. ALTER TABLE employees   SET UNUSED COLUMN sal;
F. Select MAX(sal)   FROM employees   WHERE department_id = 20;

单项选择题What is true about sequences?（）

A. The start value of the sequence is always 1.
B. A sequence always increments by 1.
C. The minimum value of an ascending sequence defaults to 1.
D. The maximum value of descending sequence defaults to 1.

单项选择题The DBA issues this SQL command: What privileges does the user Scott have at this point?（）

A. No privileges.
B. Only the SELECT privilege.
C. Only the CONNECT privilege.
D. All the privileges of a default user.