[b]INSERT INTO Vehicle_Ordered[/b] VALUES
        (‘8’ ,'9', '3', 

TO_DATE('07-SEP-06:10:00','YY-MON-DD:HH24:MI'),
TO_DATE('07-SEP-06:14:00','YY-MON-DD:HH24:MI'),

Select SUM((Vehicles_Ordered.Hire_End_Time-Vehicles_Ordered.Hire_Start_Time)*24*Vehicle.Hourly_Hire_Rate)    
From Customer, Order_Record, Vehicles_Ordered, Staff, Vehicle
Where Customer.Customer_No = '5'
And Customer.Customer_No = Order_Record.Customer_No
And Order_Record.Order_No = Vehicles_Ordered.Order_No
And Vehicles_ordered.Staff_No = Staff.Staff_No;

Select (Vehicles_Ordered.Hire_End_Time-Vehicles_Ordered.Hire_Start_Time)*24*4 
From Customer, Order_Record, Vehicles_Ordered, Staff, Vehicle
Where Customer.Customer_No = '5'
And Customer.Customer_No = Order_Record.Customer_No
And Order_Record.Order_No = Vehicles_Ordered.Order_No
And Vehicles_ordered.Staff_No = Staff.Staff_No;

CREATE TABLE Staff
(Staff_No 		CHAR(5) 	NOT NULL,
Title			CHAR(4) 	NOT NULL,
First_Name 		VARCHAR2 (15) 	NOT NULL,
Surname 		VARCHAR2 (15) 	NOT NULL,
House_Number 		VARCHAR2 (15) 	NOT NULL,
Street 			VARCHAR2 (30) 	NOT NULL,
Town 			VARCHAR2 (30) 	NOT NULL,
Postcode 		CHAR(8) 	NOT NULL	UNIQUE,
Contact_Number 		CHAR(12) 	NOT NULL,
National_Insurance_No 	CHAR(10) 	NOT NULL 	UNIQUE,
Driving_License_No	CHAR(16)	NOT NULL 	UNIQUE,
Date_Joined_Company 	DATE 		NULL,
Hourly_Rate 		DECIMAL(8,2) 	NOT NULL 
  constraint HourlyRateRange CHECK (Hourly_Rate between 0 and 50),
Position 		VARCHAR2(30) 	NOT NULL,
Primary key (Staff_No));

Select SUM((Vehicles_Ordered.Hire_End_Time-Vehicles_Ordered.Hire_Start_Time)*24*Vehicle.Hourly_Hire_Rate)    
From Customer, Order_Record, Vehicles_Ordered, Staff, Vehicle
Where Customer.Customer_No = '5'
And Customer.Customer_No = Order_Record.Customer_No
And Order_Record.Order_No = Vehicles_Ordered.Order_No;

Select SUM((Vehicles_Ordered.Hire_End_Time-Vehicles_Ordered.Hire_Start_Time)*24*Vehicle.Hourly_Hire_Rate)    
From Customer, Order_Record, Vehicles_Ordered, Staff, Vehicle
Where Customer.Customer_No = '5'
And Customer.Customer_No = Order_Record.Customer_No
And Order_Record.Order_No = Vehicles_Ordered.Order_No
And Vehicles_Ordered.Vehicle_No = Vehicle.Vehicle_No;

SQL> select * from order_record;

ORDER_NO   CUSTOMER_N
---------- ----------
3          5

SQL> select * from vehicle;

VEHICLE_NO HOURLY_HIRE_RATE
---------- ----------------
8                       175
3                       400

SQL> select * from vehicles_ordered;

VEHICLE_NO STAF ORDER_NO   HIRE_STAR HIRE_END_
---------- ---- ---------- --------- ---------
8          9    3          06-SEP-07 06-SEP-07
3          1    3          01-DEC-07 01-DEC-07

SQL> select  
sum((Vo.Hire_End_Time-Vo.Hire_Start_Time)*24*v.hourly_hire_Rate) 
as invtotal
  2  from     Customer c,
  3       Order_Record o,
  4       Vehicles_Ordered vo,
  5       vehicle v     
  6  where C.Customer_No = O.Customer_No and 
  7  o.order_no =   vo.order_no and 
  8  v.vehicle_no = vo.vehicle_no;

  INVTOTAL
----------
      1100