How to validate non commited items in detail block.

Question

Hi All,
I have a Detail block with 10 rows and 2 columns. the select of items is based on LOV. If i select One item in one row, then the user cannot select the same item again in other rows. either I need to not show the selected item in LOV or I need to raise form trigger failure and ask him to change values. This is to be done before commiting the items. Can anyone, please suggest me some way or triggers I can use.
Thank you.

Answer 1

If the process is done by a key-commit trigger or a when button-pressed trigger then it is simple . But if there is no such trigger then you should create it because it is more convenient to make controls inside key-commit rather than in pre-update or pre-insert because these triggers do not accept restricted built-ins.
To validate your items just loop through the list of records and compare the values to the one you are on. Then if there are no match then you go to the next record to search for.
Something like this :
declare
v_current_value_to_compare varchar2(100);
v_record pls_integer;
begin
go_block('detail_block_name');
first_record;
while :system.last_record = 'FALSE' loop
loop
next_record;
v_current_value_to_compare := :detail_block_name.item_name;
v_record := :system.trigger_record;
if :detail_block_name.item_name = v_current_value_to_compare then
-- make your control here
end if;
exit when :system.last_record = 'TRUE';
end loop;
go_record(v_record);
end loop;
end;