Re: a explain plan question

You are correct, the NL is not good, I changed to hash join and the query
runs in 50 minutes.

Thanks

Alex



On 1/30/07, LS Cheng <exriscer@xxxxxxxxx> wrote:


doesnt look very good plan

TUD_FEDIA is accessed first then from that it eliminates partitions
(partition start/stop KEY), the problem seems nested loop, how many rows is
TU_FEDIA returning?




On 1/30/07, Remigiusz Soko?owski <rems@xxxxxxxx> wrote:

>
> >
> > Execution Plan
> > ----------------------------------------------------------
> >    0      SELECT STATEMENT Optimizer=CHOOSE (Cost=1022392 Card=934
> > Bytes=49502)
> >    1    0   SORT (GROUP BY) (Cost=1022392 Card=934 Bytes=49502)
> >    2    1     NESTED LOOPS (Cost=814767 Card=182275095
> Bytes=9660580035)
> >    3    2       TABLE ACCESS (FULL) OF 'TUD_FEDIA' (Cost=3 Card=30
> > Bytes=480)
> >    4    2       PARTITION RANGE (ITERATOR)
> >    5    4         TABLE ACCESS (FULL) OF 'TUH_NVPAGINA' (Cost=27159
> > Card=5992606 Bytes=221726422)
> >
> > I was wondering how to read this plan, the order of steps. From old
> > set autotrace trace exp it seems to me that step 5 is the first step?
> >
> >    5    4         TABLE ACCESS (FULL) OF 'TUH_NVPAGINA' (Cost=27159
> > Card=5992606 Bytes=221726422)
> >
> AFAIK the first most nested line is the first line (in this example the
> one indicated by You)
>
> Regards
> Remigiusz
>
> --
> ---------------------------------------
> Remigiusz Sokolowski <rems@xxxxxxxx>
> WP/PTI/DIP/ZAB (+04858) 52 15 770
> MySQL  v.  4.x
> Oracle v. 10.x
> ---------------------------------------
>
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>
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>

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