Question abt. combo box and database

Question

Hi. I have two combo boxes, A and B. Items in A is obtained from table X, Items in B is obtained from table Y. But, the problem is that whatever appears in combo box B should not contain those in combo box A. How do i go about doing this? Note that values in table X come from values in table Y.Here's an example:
(this is I currently have)
Combo X             Combo Y
Apple            Mango
Orange           Kiwi Fruit
Pineapple        Apple
Kiwi Fruit        
Mango          (this is I WANT)
Combo X                  Combo Y
Orange                  Mango
Pineapple               Kiwi Fruit
                        ApplePlease help and thanks in advance.

Answer 1

hi....
First of all, I've designed the two combo boxes with Add/Delete buttons in the GUI. I'm using JSP to retrieve values from database table into my combo boxes.
Actually, I have the two combo boxes already. I have already got the items inserted into combo A from table X using JSP. I am thinking of getting all the values in combo box B from the table Y first, then maybe store them in an array or something, b4 comparing those values with that from combo box A, eliminate those existing in combo box A, and the rest will be stored in combo B.
I do not know exactly how to store values i obtained from table to an array and how to compare arrays.
hope u understand what i'm trying to say, please help if possible, thanks.