no. I have seen them recently with range scans on both tables. I think it might be because I have filters on table A, which returns only a small number of records, then it hashes the large table and scans with a range scan.
I never saw this in 8i. how much did they change the CBO in 9?
>
> From: Mladen Gogala <mladen_at_wangtrading.com>
> Date: 2004/05/04 Tue PM 03:04:28 EDT
> To: oracle-l_at_freelists.org
> Subject: Re: hash join and nested loop join in an oltp query
>
>
> On 05/04/2004 02:43:13 PM, ryan.gaffuri_at_cox.net wrote:
> >
> > what types of cases make hash joins superior to nested loops? I see them alot in batch processing when I need > to join most of the rows, but I am see them now when I return a small subset of rows.
>
> Well, if you have to use full table scan to retrieve rows from one of the tables,
> there is a strong probability that hash join will be
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Received on Tue May 04 2004 - 15:19:46 CDT
