RE: Chained vs. migrated rows - Any easy way to tell the

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Date: Tue, 18 Nov 2008 08:32:01 -0500
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Ah... Thanks. I should just leave the dba_tables.chain_cnt alone? I could clean it up dba_tables I suppose?

Not sure about Martins comment concerning object_space_usage.

Joel Patterson
Database Administrator
904 727-2546

-----Original Message-----
[] On Behalf Of Martin Berger Sent: Tuesday, November 18, 2008 7:44 AM To: ORACLE-L
Subject: Re: Chained vs. migrated rows - Any easy way to tell the

would it be save to run
DBMS_SPACE.OBJECT_SPACE_USAGE to check for chain_pcent > 0 without disturbing DBMS_STATS at all?

just a guess - never tried yet.
And I also doesn't see a valid answer for the question between chained and migrated rows there.


Martin Berger

Am 06.11.2008 um 10:35 schrieb Christian Antognini:

> Hi Joel
>> The difference between dba_tables.chain_cnt and what is contained
>> in chained_rows table now is still a mystery. Stats are collected
>> nightly.
> DBMS_STATS doesn't compute the value chain_cnt. Therefore, there are
> two
> possibilities:
> 1) dba_tables.chain_cnt = 0
> 2) dba_tables.chain_cnt > 0
> If 1, either the table doesn't contain chained/migrated rows or
> was never used to compute statistics for it.
> If 2, at some time in the past the statistics were compute with
> Since DBMS_STATS doesn't compute it, you see the value at the time of
> the last execution of ANALYZE.
Received on Tue Nov 18 2008 - 07:32:01 CST

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