Update Multiple Columns when concerned about redo/undo log sizes.

Question

Hi ,
I have update statements that updates multiple columns at once if any of them is changed. What I see that even though the value of column is not changed it still increases the redo size.
Below is a sample code similar to the ones in my code. Basically I check whether there is a difference in any of the columns to be updated and update all of them.
Is there a way to improve redo log size without splitting the update statement for every column that I will be updating. Redo/Undo log size is a concern for us..
  For i In 1.rec.Count Loop
    Update employees e
       Set e.first_name = rec(i).first_name, e.last_name = rec(i).last_name
     Where e.first_name != rec(i).first_name
        Or e.last_name != rec(i).last_name;
  End Loop;My database is 10g.

Answer 1

Muhammed Soyer wrote:
Redo/Undo log size is a concern for us..You are worried about the wrong thing.
If you are concerned about the amount of undo and redo, you should be less concerned about the small diffrence between updating 1 or 3 columns and remove the loop that is contributing to a massive increase in both undo and redo.
Re: global temporary table row order
Name                                  Run1        Run2        Diff
STAT...undo change vector size     240,500   6,802,736   6,562,236
STAT...redo size                 1,566,136  24,504,020  22,937,884Run2 shows what adding a loop to a regular SQL statement will do to undo and redo. It made the redo used 15 times greater and the undo almost 30 times greater.