more on sql! - Hiya guys, I have a quick SQL question, I have a database of rental prices that have different values for

add up all "prices" from "prices table" between "from date" and "to date" for the item being rented

id         item
1          Rental Item 1
2          Rental Item 2
etc...

id   rental_id   from         to           price
1    1           2010-01-01   2010-03-31   9.99
2    1           2010-04-01   2010-06-30   15.99
etc....

SELECT SUM(`price`) as "Total Price"
FROM rental_prices
WHERE `rental_id` = '1'
AND `from` >= '2010-03-30'
AND `to` <= '2010-04-05';

set date = '2010-03-30';
while(date < '2010-04-05'){
  SELECT `price` FROM rental_prices WHERE `from` >= 'date'
AND `to` <= 'date'; //ie find the price for that date only
 TotalPrice = TotalPrice + `price`; //increment total price
  increase `date` by 1 day; // increment the date to go to start of while clause and find next days rental price.
}

SELECT SUM(`price`) as "Total Price"
FROM rental_prices
WHERE `rental_id` = '1'
AND `from` <= '2010-03-30'
AND `to` >= '2010-04-05';

SELECT SUM(  `price`  )  AS  "Total Price"
FROM rental_prices
WHERE  `rental_id`  =  '1'
AND  `from`  <=  '2010-03-30'
UNION 
SELECT SUM(  `price`  )  AS  "Total Price"
FROM rental_prices
WHERE  `rental_id`  =  '1'
AND  `to`  >=  '2010-04-05'