Oracle Database 12c: SQL Fundamentals — Question 40
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.
2) The order date cannot have null values and the default should be the current date.
3) The order amount should not be less than 50.
4) The order status will have values either shipped or not shipped.
5) The order payment mode should be cheque, credit card, or cash on delivery (COD).
Which is the valid DDL statement for creating the ORD_DETAIL table?
Answer options
- A. CREATE TABLE ord_details (ord_id NUMBER(2) CONSTRAINT ord_id_nn NOT NULL, 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')));
- 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), 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), ord_date DATE NOT NULL DEFAULT SYSDATE, 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')));
Correct answer: C
Explanation
Option C is correct because it correctly defines 'ord_id' as a PRIMARY KEY, ensuring uniqueness and non-nullability. Options A and B incorrectly use UNIQUE and NOT NULL without a primary key, and option D does not define 'ord_id' as a primary key, violating the requirement for uniqueness.