It can be inferred that the author's attitude toward cell phone yakking is_________ .
A. approving
B. disapproving
C. encouraging
D. indifferent
第1题:
Review the definition of the phone_list view.CHEATE OR REPLACE ALGORITHM=MERGE DEFINER= ‘root‘@localhost‘ SQL SECURITY DEFINER VIEW ‘phone_list‘ AS SELECTe . id as id ‘e . first_name AS ‘first_name‘ ‘e . last_name AS ‘last_name‘ ‘coalesce ( ph1.phone_no, ‘ – ‘) AS ‘office_no‘ ‘coalesce (ph2 .phone_no, ‘ – ‘) AS ‘cell_no‘ FROM employees e LEFT JOIN employee_phone ph1 ON ph1.emp_id = e.id AND ph1.type = ‘office‘ LEFT JOIN employee_phone ph2 ON ph2 .emp_id = e.id AND ph2 .type = ‘mobile‘The tables employees and employee_phone are InnoDB tables;all columns are used in this view. The contents of the phone_list view are as follows: Mysql> select * from phone_list; 1 row in set (0.00 sec)Which method can you use to change the cell_no value to ‘555-8888‘ for John Doe?()
A.INSERT INTO employee_phone (emp_id, phone_no, type) VALUES (1, ‘555-8888‘,‘mobile‘)
B.UPDATE phone_list SET cell_name ‘555-8888‘ WHERE first_name= ‘John‘ and last_name= ‘Doe‘
C.DELETE FROM phone_list WHERE first_name= ‘John‘ and last_name= ‘Doe‘; INSERT INTO phone_list (first_name, last_name, office_no, cell_no) VALUES (‘John‘ , ‘Doe‘ , ‘x1234‘ , ‘555-8888)
D.UPDATE employee_phone SET phone_no= ‘555-8888‘ where emp_id=1
第2题:
A.4Cell,4-6小时
B.6Cell,6-8小时
C.3Cell,4-6小时
D.8Cell,6-8小时
第3题:
传输速率为500kbit/s的CAN总线,理论上CAN低的显性电压为
A.1.5V
B.2.5V
C.3.5V
D.5V
第4题:
A.16mm,1.1kg(3cell)
B.18mm,1.4kg(3cell)
C.18mm,1.1kg(3cell)
D.16mm,1.4kg(3cell)
第5题:
第6题:
5、传输速率为500kbit/s的CAN总线系统中,CAN_L对电源短路,那么该CAN总线的数据传输无法进行。