When-Validate-Item and Go_Block/Execute Query dilemma

Question

Hey there folks -- Probably not a surprise question on this forum. I did try to search for this and came up with a few posts but did not find any solutions. Hopefully, I was also doing the correct way to search on this forum. If this is a post for the nth time on this issue, I apologize.
So, I have 2 blocks:
1. Control Block that contains the STUDENT_ID field (Database Item = 'N')
2. Database block that contains the STUDENT_ID field (Database Item = 'Y' and many other fields)
My goal is do an Execute_Query if User enters the Student ID and either presses TAB or places the MOUSE in the database block and display the record if it exists. As we know, a Go_Block is not allowed in When-Validate-Item. So, I went one step further to "simulate" this. The problem is that I am still firing the Execute-Query when the record has already been retrieved. Here is what I have so far. So, the Key-Next-Item trigger works fine if User enters a Student ID and presses tab. It also works fine if User clicks on the STUDENT_BK as the When-New-Block-Instance trigger fires which in turn calls the Key-Next-Item. The problem occurs when after record has been retrieved and User clicks on control.student_id and then comes and clicks on the STUDENT_BK, the KEY-NEXT-ITEM trigger fires again.
Suggestions or pointers would be more than welcome.
Thanks!
CONTROL.student_id.Key-Next-Item
  if :control.student_id is not null and :SYSTEM.BLOCK_STATUS != 'CHANGED' then
    next_block;
    clear_block(NO_COMMIT);
    execute_query;
  else
    show_alert('Please enter Student ID');
  end if;
STUDENT_BK.When-New-Block-Instance
go_item('control.student_id');
do_key('next_item');

Answer 1

Yeah... I wrote before I tried it out. The GET_ITEM_PROPERTY('ITEM', previousitem) didn't work the way I thought it did. After I posted that, I tried it out and it was a complete failure.
I guess what I am thinking now, is in your STUDENT_BK block, do you only want to EXECUTE_QUERY if the :STUDENT_ID does not match the :CONTROL.STUDENT_ID? If that is true, then all you would have to do is to change your KEY-NEXT logic to include the
if STUDENT_BK.STUDENT_ID != :CONTROL.STUDENT_ID then
  -- original logic
  go_item('control.student_id');
  do_key('next_item');
end if;The more I think about it, this should work for you. You said that you had two requirements: Entered a student id in the control block and tabbed or entered the database block. If you add the check of the student id then that should take care of your second requirement. If they enter the database block and the id's don't match then it will execute the query, else they already have the record displayed for them so you don't need to do anything.
Edited by: MLBrown on Nov 19, 2012 3:08 PM