Re: explain plan differences...

From: Jonathan Lewis <jonathan_at_jlcomp.demon.co.uk>
Date: Thu, 20 Dec 2001 10:15:55 -0000
Message-ID: <1008850831.29984.0.nnrp-01.9e984b29@news.demon.co.uk>

A possible indicator of this comes from the lines:

>> 10 3 TABLE ACCESS (BY INDEX ROWID) OF 'TBL_ANGEBOT'

                                    (Cost=1 Card=2049 Bytes=26637)


>>   12    2       TABLE ACCESS (BY INDEX ROWID) OF 'TBL_ANGEBOT'

                                    (Cost=1 Card=2196 Bytes=28548)

The expected number of rows returned (card) is larger in one plan than the other. This may be because the access has appeared in a different place in the place, but it may simply mean that the statistics after the exp/imp are slightly different.

--
Jonathan Lewis
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Connor McDonald wrote in message <3C2104E9.1E4E_at_yahoo.com>...


>

>When you exp/imp, the second schema will have rows more tightly packed,

>indexes freshly built et al - if the stats reflect this, then the plans

>could be different.

>

Received on Thu Dec 20 2001 - 04:15:55 CST