Re: CREATE INDEX: PARALLEL flag influences index usage

On Fri, 11 Mar 2005 16:17:41 +0100, "Robert Klemme" <bob.news_at_gmx.net> wrote:

>Now my question is, what's happening here? How does the option influence
>the execution plan and why does the optimizer choose the slow variant if
>PARALLEL is switched off? Thanks a lot for any hints!

You need to do some analysis, and you are the only one who can do it, as this group is not clairvoyant.
We need you to run (and post) the EXPLAIN PLAN for both statements, alternatively you can set event 10053 level 1 in your session (alter session set event = "10053 trace name context forever, level 1") which will force the optimizer to generate a trace file with a break down of it's decisions.
Then having a copy of the parallel settings would also be handy.

Apart from that, the fact you seem to state you need to parallellize lookups on an index with only 17000 measly rows seems to indicate there is something seriously wrong at your site, and you may be curing symptoms only right now.

--
Sybrand Bakker, Senior Oracle DBA