I dont know why the pl/sql don not use the value of the item, can sameone help me please?

My Apex Application has one main page where the user can see all entries, if he want to change he clicks on the left button and go to the detail side.

The main page

If the user load the detail page a dynamic action Starts and the PL/SQL Function body do his job.

declare
  v_DB_ZAUE number;
begin 
  SELECT COUNT(*) INTO v_DB_ZAUE FROM DB_ZAUE WHERE CCB_ID = :P21_CCB_ID;
        
  return v_DB_ZAUE;
end;

Now starts my problem, on the detail page is the value of the item P21_CCB_ID Displayed put the PL/SQL Code ignores it. Because if the PL/SQL Code works the field with the name Temp were 1 and not 0.

Here is the detail page

PS: I check the names of all variables there are all ok

Thanks for help

>Solution :

I presume you didn’t put P21_CCB_ID into Dynamic Action’s Items to Submit property, so I’d suggest you to do so.

Because, without it, P21_CCB_ID item’s value isn’t in session state so it (query) behaves as if it doesn’t exist (or uses value that was previously put into session state, and that’s not what you really want).