Validated Previous row data

Question

Hi,
I need to validate the cell in my application using raise application error's
My Requirement is like this
There are 4 Columns
"Incoming", "Design", "Build","Test","Release"
non of the previous phase must be null, if any of the previous phase is null it must trough a error. I am trying to do like this using a if statement
wwv_flow.g_f04(vRow)) //Incoming
to_number(wwv_flow.g_f05(vRow)) //Design
to_number(wwv_flow.g_f06(vRow)) //Build
to_number(wwv_flow.g_f07(vRow)) //Test
to_number(wwv_flow.g_f08(vRow)) //Release
IF to_number(wwv_flow.g_f04(vRow)) IS NULL AND to_number(wwv_flow.g_f05(vRow)) IS NOT NULL Then
RAISE_APPLICATION_ERROR(-20000,'Previous Phase Incoming-Doc is null, Cannot Proceed Furthere');
END IF;
but this will take to lot of condition how to validate this please suggest
Thanks
Sudhir

Answer 1

Sudhir
If the values were in an array (based at 1, finish at N>1), you want a loop like this (I have used an array called x() for simplicity). This approach is also easy to scale to 10, 20 or 1000 stages:
for i in 1..n loop
  if x(i) is null and x(i+1) is not null then
     RAISE_APPLICATION_ERROR(-20001, ,'Phase '|| phase_name(i+1) ' is set and previous phase ' || phase_name(i) || ' is null, Cannot Proceed Further');
  end if;
end loop;Note that this finds the first transition from null to set; it doesn't try to show all the values that should have been set:
Incoming: set
Design: null
Build: null:
Test: set
Release: set
The error message would be "Phase Test is set and previous phase Build is null ..." - no mention of the Design phase. Of course you could easily build a string that told you ALL previous null sets.
HTH
Regards Nigel