ocp試題解析：11g-1Z0-051-v9.02-036題，完整題庫請點擊這里聯(lián)系老師咨詢了解

36. Examine the following SQL commands:

SQL>CREATE TABLE products (

prod_id NUMBER(3) CONSTRAINT p_ck CHECK (prod_id > 0),

prod_name CHAR(30),

prod_qty NUMBER(6),

CONSTRAINT p_name NOT NULL,

CONSTRAINT prod_pk PRIMARY KEY (prod_id));

SQL>CREATE TABLE warehouse (

warehouse_id NUMBER(4),

roomno NUMBER(10) CONSTRAINT r_id CHECK(roomno BETWEEN 101 AND 200),

location VARCHAR2(25),

prod_id NUMBER(3),

CONSTRAINT wr_pr_pk PRIMARY KEY (warehouse_id,prod_id),

CONSTRAINT prod_fk FOREIGN KEY (prod_id) REFERENCES products(prod_id));

Which statement is true regarding the execution of the above SQL commands?

A. Both commands execute successfully.

B. The first CREATE TABLE command generates an error because the NULL constraint is not valid.

C. The second CREATE TABLE command generates an error because the CHECK constraint is not valid.

D. The first CREATE TABLE command generates an error because CHECK and PRIMARY KEY

constraints cannot be used for the same column.

E. The first CREATE TABLE command generates an error because the column PROD_ID cannot be used

in the PRIMARY KEY and FOREIGN KEY constraints.

Answer: B

試題解析：

第一個命令報錯，因為CONSTRAINT p_name NOT NULL不能定義為表級，第一個命令里的CHECK和主鍵約束能用在相同的列上。

A錯誤，因為第一個報錯。

B正確，NOT NULL不能定義為表級，只能定義為列級

C錯誤，between可以用在check約束里

D錯誤，check和主鍵約束可以用在同一列

E錯誤，可以把主鍵作為其他表的外鍵