Update a Column during Insert

Question

A row is being inerted by GUI with a column as NULL. DB need to update this column.
Trigger will create a mutating Error.
Can you please help me how to update the column.
(Using Oracle 10g)

Answer 1

>
UPDATE test
SET column6 = '100'
WHERE column1 = :new.column1;
END trig_test;
As updating the same table, getting Mutating Error.
>
Yes - you can't update the same table and you don't want to use the AFTER trigger.
Jeneesh's uses a BEFORE INSERT .. FOR EACH ROW trigger and sets the new value. So use his code to
create or replace trigger test_trig before insert
  on test for each row
  begin
   if :new.column6 is null then
      :new.column6 := '100';
   end if;
  end;And why are you storing what appears to be a number in a VARCHAR2 datatype? Store numbers in numeric columns.