Validation error on numeric field

Question

Hi, I am very new to Oracle Database and have only recently started learning SQL, PL/SQL and Apex.
I have created a very simple stock control application with a report that lists the quantity of parts in locations with a button on each row that allows the user to "Take Out" a quantity of that part from the location. When you click this button a new form is displayed (showing as read-only fields) the information of the selected part loaded from the database including the "Current Quantity" and a new number field "Take Out Quantity" which is the only field the user can edit.
I have added some simple validation to prevent the user from entering a "Take Out Quantity" that is greater than the "Current Quantity" (which would in the real world be impossible as you cannot have a negative quantity of an item). My code is as follows:
if :P11_TOQUANTITY > :P11_CURRQTY then
return false;
else
return true;
end if;
however I get some very strange results in that it appears to only validate against the first digit of the current quantity. e.g.
Current Quantity = 54
New Quantity = 6 Returns an error
but
Current Quantity = 54
New Quantity = 5 is ok
In fact I can enter any number <= 5 but cannot enter number greater than 5 but I should be able to enter any number <= 54
Can any one suggest what I might be doing wrong?
Thanks
Richard

Answer 1

Thanks Alex,
That's great, I have done as you suggested and it works perfectly now. I knew it was something simple but I just could not work out what. I didn't realise that all fields on the page are considered as strings.
As a result I also tried to change my other protected fields on the screen from Display As Text Field to Display Only and changed Read Only Condition Type from always to none but then it doesn't work properly as the screen seems to lose the values once I enter a "Take Out" value and press the submit button causing the validation to fail. So I assume I had done it correctly the first time?