单项选择题
What is true about updates through a view?()
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.
点击查看答案
相关考题
-
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?()
A.A
B.B
C.C
D.D
E.E -
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?()
A.randomly
B.ascending by date
C.descending by date
D.ascending alphabetically
E.descending alphabetically -
单项选择题
Which is an iSQL*Plus command?()
A.INSERT
B.UPDATE
C.SELECT
D.DESCRIBE
E.DELETE
F.RENAME
