【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.
【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...