多项选择题

Examine the SQL statements that creates ORDERS table:

For which columns would an index be automatically created when you execute the above SQL statement? （）

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

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单项选择题

Examine the data of the EMPLOYEES table.
EMPLOYEES (EMPLOYEE_ID is the primary key. MGR_ID is the ID of managers and refers to the EMPLOYEE_ID)
EMP_NAME DEPT_ID MGR_ID JOB_ID SALARY
EMPLOYEE_ID
101 Smith 20 120 SA_REP 4000
102 Martin 10 105 CLERK 2500
103 Chris 20 120 IT_ADMIN 4200
104 John 30 108 HR_CLERK 2500
105 Diana 30 108 HR_MGR 5000
106 Bryan 40 110 AD_ASST 3000
108 Jennifer 30 110 HR_DIR 6500
110 Bob 40 EX_DIR 8000
120 Ravi 20 110 SA_DIR 6500
Which statement lists the ID, name, and salary of the employee, and the ID and name of the employee's manager, for all the employees who have a manager and earn more than 4000?（）

A. SELECT employee_id "Emp_id", emp_name "Employee", salary, employee_id "Mgr_id", emp_name "Manager" FROM employees WHERE salary > 4000;
B. SELECT e.employee_id "Emp_id", e.emp_name "Employee",
C. salary,
D. employee_id "Mgr_id", m.emp_name "Manager" FROM employees e, employees m WHERE e.mgr_id = m.mgr_id AND e.salary > 4000;

单项选择题

Which statement explicitly names a constraint?（）

A. ALTER TABLE student_grades   ADD   FOREIGN KEY (student_id) REFERENCES students(student_id);
B. ALTER TABLE student_grades   ADD CONSTRAINT NAME = student_id_fk   FOREIGN KEY (student_id) REFERENCES students(student_id);
C. ALTER TABLE student_grades   ADD CONSTRAINT student_id_fk   FOREIGN KEY (student_id) REFERENCES students(student_id);
D. ALTER TABLE student grades   ADD NAMED CONSTRAINT student_id_fk   FOREIGN KEY (student_id) REFERENCES students(student_id);
E. ALTER TABLE student grades   ADD NAME student_id_fk   FOREIGN KEY (student_id) REFERENCES students(student_id);

单项选择题

You want to display the titles of books that meet these criteria:
1. Purchased before January 21, 2001
2. Price is less then $500 or greater than $900
You want to sort the results by their data of purchase, starting with the most recently bought book.
Which statement should you use?（）

A.
B.
C.
D.

Examine the SQL statements that creates ORDERS table: For which columns would an index be automatically created when you execute the above SQL statement? （）

相关考题

Examine the SQL statements that creates ORDERS table:

For which columns would an index be automatically created when you execute the above SQL statement? （）