Comments on: Data block corruption cleared with alter system flush buffer_cache http://andrewfraserdba.com/2007/04/19/data-block-corruption-cleared-with-alter-system-flush-buffer_cache/ Oracle DBA (plus SQL Server) Wed, 14 Jul 2010 09:54:31 +0000 http://wordpress.org/?v=2.9.2 hourly 1 By: Lutz Hartmann http://andrewfraserdba.com/2007/04/19/data-block-corruption-cleared-with-alter-system-flush-buffer_cache/#comment-52 Lutz Hartmann Mon, 10 Dec 2007 23:09:59 +0000 http://andrewfraser.wordpress.com/2007/04/19/data-block-corruption-cleared-with-alter-system-flush-buffer_cache/#comment-52 Hi Andrew, this is very interesting. I had a similar efect at a customer's site recently with 10gR2 where I encountered an object that "didi not exist any more". It was possible to describe it but a SELECT COUNT(*) returned an ORA-600. There were no extents in DBA_EXTENTS and it was not possible to DROP it: also ORA-600. Since my customer did not use RMAN we ended up with a full export except this one object and full import into a new DB. Obviousely the Data Dictionary was corrupted. I guess it's a BUG! Or is it a feature? =;-) Lutz Hi Andrew,
this is very interesting. I had a similar efect at a customer’s site recently with 10gR2 where I encountered an object that “didi not exist any more”.
It was possible to describe it but a SELECT COUNT(*) returned an ORA-600.
There were no extents in DBA_EXTENTS and it was not possible to DROP it: also ORA-600.

Since my customer did not use RMAN we ended up with a full export except this one object and full import into a new DB.
Obviousely the Data Dictionary was corrupted.

I guess it’s a BUG!
Or is it a feature?
=;-)
Lutz

]]> By: Lutz Hartmann http://andrewfraserdba.com/2007/04/19/data-block-corruption-cleared-with-alter-system-flush-buffer_cache/#comment-51 Lutz Hartmann Wed, 16 May 2007 07:27:30 +0000 http://andrewfraser.wordpress.com/2007/04/19/data-block-corruption-cleared-with-alter-system-flush-buffer_cache/#comment-51 Hi Anrew, it is always a good idea to check proactively for corrupt block (both physical & logical corruption) with RMAN. Pls see my post about it: http://sysdba.wordpress.com/2006/04/05/how-to-check-for-and-repair-block-corruption-with-rman-in-oracle-9i-and-oracle-10g/ =;-) Lutz Hi Anrew,
it is always a good idea to check proactively for corrupt block (both physical & logical corruption) with RMAN.
Pls see my post about it:
http://sysdba.wordpress.com/2006/04/05/how-to-check-for-and-repair-block-corruption-with-rman-in-oracle-9i-and-oracle-10g/

=;-)
Lutz

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