How to fetch last record from the table to display in screen painter?

Question

Hi Gurus,
              I have a requirement where i have to fetch the last record value in the table.
I have a screen where the TEXT name is REQUEST and I/P field name is REQ and SAVE push button.
In this I/P field automatically 1 should display when i excecute the program and when i save this, the request number should turn to 2 that is dynamically..once agin save then 3 and so on....and this 1, 2, 3 will be storeing in table.
I have succeeded till generating the values dynamically and saving in the table like 1 is displayed and when i click save it is changeing to 2..but the problem is when i am coming out of program and logon again the request number is again displaying as 1 rather it has to start with 4 because already 3 request are there in the table.
My code is...
Table zsave.
data declarations....
data req type i.
req = 0.
req = zsave-req.
PROCESS BEFORE OUTPUT
req = 0.
select req into table fun_st from zsave.
req = zsave-req.
zsave-req = req.
req = zsave-req + 1.
PAI
req = zsave-req + 1.
zsave-req = req.
when 'save'.
wa_funst-req = zsave-req.
Please can you provide me with the solution....answer will be rewared.
THKS

Answer 1

Can you tell me, when updaing the ZSAVE table with the counter value are you modifying the exisiting value or inserting the value as new record?
From the code in your first post, i see that you are extracting records into internal table but when you are moving to variable REQ, you are moving from table work area which is blank, so everytime when you execute it may be starting as 0.
Hope below code can help you understand on handling your requirement
Global Declaration:
>DATA: l_req TYPE i. 
PBO:
  SELECT MAX( req ) INTO l_req FROM zsave.
  l_req = l_req + 1.
PAI:
  DATA: wa TYPE zsave.
  CASE ucomm.
  WHEN 'SAVE'.
    wa-req = l_req.
    INSERT zsave FROM wa.
  ENDCASE.