Secondary indexes contain a logical rowid in version 9+. Oracle looks fo=
r
row at or near indexed logical rowid. If it finds it great. If it does =
not
find the row then the primary index structure is searched using the PK.
Hope this clears up any confusion caused by my reply. The manual contain=
s
more details of exactly what Oracle does and the cost of stale guesses.
-- Mark D Powell --
-- --Original Message-- --
From: oracle-l-bounce@(protected)
[mailto:oracle-l-bounce@(protected)]On Behalf Of Jared Still
Sent: Wednesday, April 28, 2004 1:51 PM
To: Oracle-L Freelists
Subject: Re: RE: Index-Organized Table experiences
Guess?
What does that mean?
An IOT is essentially a b*tree that is treated as a table.
What kind of guessing would be involved?
Jared
On Wed, 2004-04-28 at 10:15, ryan.gaffuri@(protected) wrote:
> We have alot of many to many relationships. IOTs sound like a good opti=
on.
However, our many to many relationships are in a high transaction databas=
e.
I remember reading that Oracle has to 'guess ' the location of IOTs and th=
at
if you perform alot of DML those guesses can be inaccurate.
>=20
> anyone have experience with this?=20
>=20
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