Understanding Oracle Apex_Application.G_Fnn and how to use it

Question

I am quite confused with how Oracle apex_application.gfnn works and whether it only works for standard SQL reports in Oracle ApEx or only with SQL (Updateable reports, i.e. tabu

Answer 1

You're very close.

select apex_item.checkbox2(10, empno) select_me,
apex_item.text(20, empno) empno,
apex_item.text(30, ename)||apex_item.hidden(50, empno) ename
from emp

I'm concatenating the hidden item since i don't want it in its own column. Messes with the layout.
Also, the hidden item is there because of how checkboxes work. Checkboxes only submit their values for checked items. This would mean that array 10 has 3 values. The other arrays would still contain the values for all rows.
This is why i added the hidden empno again: so we can match the checked values to the other rows.

On submit process:

DECLARE
   v_empno emp.empno%TYPE; 
   v_ename emp.ename%TYPE;
BEGIN
   --f10: checkbox
   --f20: empno
   --f30: ename
   --f50: empno again
   for i in 1..apex_application.g_f10.count
   loop
      for j in 1..apex_application.g_f50.count loop
         if apex_application.g_f10(i) = apex_application.g_f50(j) 
         then         
            -- access values for the selected rows in the other arrays
            v_empno := apex_application.g_f20(j);
            v_ename := apex_application.g_f30(j);

            apex_debug_message.log_message('Employee: '||v_empno||' - '||v_ename);
         end if;
      end loop;
   end loop;
END;

Run page, enable debug, select records 2, 4 and 6, submit.

Debug output:

All you now need to do is put your processing in that loop.