OCP-1Z0-051-V9.02-33题

33. You want to create an ORD_DETAIL table to store details for an order placed having the following

business requirement:

1) The order ID will be unique and cannot have null values.（唯一+非空约束=主键约束）

2) The order date cannot have null values and the default should be the current date. （order date非空default sysdate）

3) The order amount should not be less than 50.（不少于50，即大于等于50）

4) The order status will have values either shipped or not shipped.（order status IN ('Shipped', 'Not Shipped'） ）

5) The order payment mode should be cheque, credit card, or cash on delivery (COD).（ order payment  mode ('Cheque', 'Credit Card', 'Cash On Delivery')）

Which is the valid DDL statement for creating the ORD_DETAIL table?

A. CREATE TABLE ord_details   

(ord_id NUMBER(2) CONSTRAINT ord_id_nn NOT NULL,   此处没有唯一约束

ord_date DATE DEFAULT SYSDATE NOT NULL,    

ord_amount NUMBER(5, 2) CONSTRAINT ord_amount_min           

CHECK (ord_amount > 50),     此处应该大于等于50

ord_status VARCHAR2(15) CONSTRAINT ord_status_chk           

CHECK (ord_status IN ('Shipped', 'Not Shipped')),    

ord_pay_mode VARCHAR2(15) CONSTRAINT ord_pay_chk           

CHECK (ord_pay_mode IN ('Cheque', 'Credit Card',                    

'Cash On Delivery')));

B. CREATE TABLE ord_details   

(ord_id NUMBER(2) CONSTRAINT ord_id_uk UNIQUE NOT NULL,   

ord_date DATE DEFAULT SYSDATE NOT NULL,    

ord_amount NUMBER(5, 2) CONSTRAINT ord_amount_min           

CHECK (ord_amount > 50),      此处应该大于等于50

ord_status VARCHAR2(15) CONSTRAINT ord_status_chk           

CHECK (ord_status IN ('Shipped', 'Not Shipped')),    

ord_pay_mode VARCHAR2(15) CONSTRAINT ord_pay_chk           

CHECK (ord_pay_mode IN ('Cheque', 'Credit Card',                    

'Cash On Delivery')));

C. CREATE TABLE ord_details   

(ord_id NUMBER(2) CONSTRAINT ord_id_pk PRIMARY KEY,   

ord_date DATE DEFAULT SYSDATE NOT NULL,    

ord_amount NUMBER(5, 2) CONSTRAINT ord_amount_min           

CHECK (ord_amount >= 50),    

ord_status VARCHAR2(15) CONSTRAINT ord_status_chk           

CHECK (ord_status IN ('Shipped', 'Not Shipped')),    

ord_pay_mode VARCHAR2(15) CONSTRAINT ord_pay_chk

CHECK (ord_pay_mode IN ('Cheque', 'Credit Card',                     

'Cash On Delivery')));

D. CREATE TABLE ord_details    

(ord_id NUMBER(2),   此处没有唯一非空约束

ord_date DATE NOT NULL DEFAULT SYSDATE,    此处报语法错误

ord_amount NUMBER(5, 2) CONSTRAINT ord_amount_min           

CHECK (ord_amount >= 50),    

ord_status VARCHAR2(15) CONSTRAINT ord_status_chk           

CHECK (ord_status IN ('Shipped', 'Not Shipped')),    

ord_pay_mode VARCHAR2(15) CONSTRAINT ord_pay_chk           

CHECK (ord_pay_mode IN ('Cheque', 'Credit Card',                   

'Cash On Delivery')));

Answer: C

D答案应该先default sysdate，后not null。

sys@TEST0910> create table t7(ord_date date not null default sysdate);

create table t7(ord_date date not null default sysdate)

                                       *

ERROR at line 1:

ORA-00907: missing right parenthesis

 

 

sys@TEST0910> create table t7(ord_date date default sysdate not null);

 

Table created.