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Home -> Community -> Usenet -> c.d.o.misc -> Re: O9i: How to create a matching index to a given query
On Apr 3, 4:29 am, Andreas Mosmann <mosm..._at_expires-30-04-2007.news-
group.org> wrote:
> sybra..._at_hccnet.nl schrieb am 02.04.2007 in
> <met2135m7p791c87nhfm0chkun8juq1..._at_4ax.com>:
>
> > In the second case you select a non-indexed column. Apparently the
> > optimizer predicts this will take less I/O. This would be a case for
> > to set event 10051.
>
> Can you point me to a place in the Oracle documentation where I can read
> about the HowTo?
> - I looked for event and there were too many results.
> - I looked for 10051 and there were no result.
>
> a better keyword than these 2 might also help a lot.
>
> > Hth
>
> Me too ;)
>
> Many thanks
>
> Andreas Mosmann
>
> --
> wenn email, dann AndreasMosmann <bei> web <punkt> de
Sybrand's comments in this thread are leading you in the right direction. Try a search on 10053 trace rather than 10051 trace. As Sybrand mentions, this trace is covered in detail in Jonathan Lewis' "Cost-Based Oracle Fundamentals" book. You will want to make certain that declared foreign keys are indexed. Keep in mind that declared foreign keys (and other constraints) can generate additional predicates that are automatically added to the original SQL statement, which could affect the plan that Oracle selects for executing the query.
Charles Hooper
PC Support Specialist
K&M Machine-Fabricating, Inc.
Received on Tue Apr 03 2007 - 06:49:40 CDT