单项选择题
A.You cannot update a view with group functions.
B.When you update a view group functions are automatically computed.
C.When you update a view only the constraints on the underlying table will be in effect.
D.When you update a view the constraints on the views always override the constraints on the underlying tables.
单项选择题 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 = Smith); What is the result when the query is executed?（）
单项选择题 The EMP table contains these columns: EMPLOYEE_ID NUMBER(4) EMPNAME VARCHAR2 (25) SALARY NUMBER(9,2) HIRE_DATE DATE You query the database with this SQL statement: SELECT empname,hire_date HIREDATE, salary FROM EMP ORDER BY hire_date; How will the results be sorted?（）
单项选择题 Which is an iSQL*Plus command?（）