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CREATE TABLE EMPLOYEE
(Employee_ID CHAR(3),
Employee_name CHAR(20),
CONSTRAINT pk_Employee PRIMARY KEY (Employee_ID));
CREATE TABLE CUSTOMER
(Customer_ID CHAR(5),
Customer_Name CHAR(20),
CONSTRAINT pk_Customer PRIMARY KEY (Customer_ID));
CREATE TABLE PRODUCT
(Product_ID CHAR(5),
Product_Name CHAR(30),
Product_Colour CHAR(10),
Product_Price CHAR(5),
CONSTRAINT pk_Product PRIMARY KEY (Product_ID));
CREATE TABLE SALES_ORDER
(Sales_order_ID CHAR(6),
Employee_ID CHAR(3),
Customer_ID CHAR(5),
Sale_Date CHAR(10),
Order_total CHAR(7),
CONSTRAINT pk_Order PRIMARY KEY (Sales_order_ID),
CONSTRAINT fk_Order FOREIGN KEY (Employee_ID) REFERENCES EMPLOYEE (Employee_ID),
FOREIGN KEY (Customer_ID) REFERENCES CUSTOMER (Customer_ID));
CREATE TABLE ORDER_LINE
(Sales_order_ID CHAR(6),
Product_ID CHAR(5),
Quantity CHAR(3),
Line_total CHAR(5),
CONSTRAINT pk_Order_Line PRIMARY KEY (Sales_order_ID),
FOREIGN KEY (Product_ID) REFERENCES PRODUCT (Product_ID));