Checking of duplicate record

Question

am wondering how to write code that will check the new item if it is already existing in the table before it can be inserted...am just new in forms. thanks.

Answer 1

According to online help, CHECK_RECORD_UNIQUENESS is only valid from the On-Check-Unique trigger and only performs what Forms does by default -- checks if the record has already been inserted into the table. Just set the Enforce Primary Key property to Yes for the block, and this happens automatically.
If you want to check right after the user enters the primary key for a new record, you can do it in the When-Validate-Item trigger:
declare
   record_count number := 0;
begin
   select count(*) into record_count from <tablename>
   where <primary_key_column> = :<block.primary_key>;
   if record_count > 0 then
      message('This record is already in the database.');
      raise form_trigger_failure;
   end if;
end;