Need validation that ensures only one item has a value.

Question

Hello,
I need a validation that ensures that only one item has a value. I want to allow a person entering information into a form to have the option to either select from a drop-down or enter something into a text box but not both.
I have found some information about validation of this type but I'm not sure how to use it. Here is what I found:
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This validation ensures that only one item (ITEM_1, ITEM_2) has a value.
Example 5:
Assume a function similar to the following exists:
create or replace function sampleValidation (p_arg in varchar2) return boolean
as
begin
if p_arg= '1' then
return true;
else
return false;
end if;
end;
A validation of type PL/SQL Expression could then reference this function returning a boolean using the following syntax:
sampleValidation(v('MY_ITEM'))
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Please let me know how to implement this or give me another way to validate.
Thanks
Linda

Answer 1

Linda,
The best is to use a Validation of type PL/SQL Function Returning Error Text like this:
BEGIN
   IF :p1_item_1 IS NULL AND :p1_item_2 IS NULL
   THEN
      RETURN 'One of the items must have a value.';
   ELSIF :p1_item_1 IS NOT NULL AND :p1_item_2 IS NOT NULL
   THEN
      RETURN 'Only one of the items must have a value.';
   END IF;
END;Denes Kubicek
http://deneskubicek.blogspot.com/
http://www.opal-consulting.de/training
http://apex.oracle.com/pls/otn/f?p=31517:1
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