【单选题】Click the Exhibit button and examine the data in the EMPLOYEES table. On the EMPLOYEES table, EMPLOYEE_ID is the primary key. MGR_ID is the ID of managers and refers to the EMPLOYEE_ID. The JOB_ID col...
A.
There is no row with dept_id 90 in the EMPLOYEES table.
B.
You cannot delete the JOB_ID column because it is a NOT NULL column.
C.
You cannot specify column names in the DELETE clause of the DELETE statement.
D.
You cannot delete the EMPLOYEE_ID column because it is the primary key of the table.
【简答题】_____ A. He lost his classmate’s homework. B. He can’t help the woman with her math. C. He broke the woman’s calculator. D. He doesn’t know where the ON button is.
【单选题】Click the Exhibit button and examine the data from the ORDERS and CUSTOMERS tables. Evaluate this SQL statement: SELECT cust_id, ord_total FROM orders WHERE ord_total > ANY(SELECT ord_total FROM order...
【单选题】Click the Exhibit button and examine the data from the ORDERS and CUSTOMERS tables. Evaluate the SQL statement: SELECT * FROM orders WHERE cust_id = (SELECT cust_id FROM customers WHERE cust_name = 'S...