Bulk Insert into Oracle database: Which is better: FOR Cursor loop or a simple Select?

Question

Which would be a better option for bulk insert into an Oracle database ? A FOR Cursor loop like

DECLARE
   CURSOR C1 IS SELECT * FROM FOO;
BEGIN
   FOR C1_R         


        

Answer 1

As you can see by reading the other answers, there are a lot of options available. If you are just doing < 10k rows you should go with the second option.

In short, for approx > 10k all the way to say a <100k. It is kind of a gray area. A lot of old geezers will bark at big rollback segments. But honestly hardware and software have made amazing progress to where you may be able to get away with option 2 for a lot of records if you only run the code a few times. Otherwise you should probably commit every 1k-10k or so rows. Here is a snippet that I use. I like it because it is short and I don't have to declare a cursor. Plus it has the benefits of bulk collect and forall.

begin
    for r in (select rownum rn, t.* from foo t) loop
        insert into bar (A,B,C) values (r.A,r.B,r.C);
        if mod(rn,1000)=0 then
            commit;
        end if;
    end;
    commit;
end;

I found this link from the oracle site that illustrates the options in more detail.