Re: Redo question

From: Jonathan Lewis <jonathan_at_jlcomp.demon.co.uk>
Date: 2006-01-04 21:50:35
Message-id: 000a01c61170$832a88d0$0200a8c0@Primary

It depends on how you're looking and,
probably, which version of Oracle.

GTTs do not cause redo, but the undo
on GTTs causes redo, so the redo records on a GTT have only one half of the usual forward/backward pair of change vectors.

You can see this easily in a block dump - but I've never looked in v$logmnr_contents to see what it does in the sql_redo and sql_undo for GTTs.

At a lightweight level, the redo entry size for an operation against a GTT will be smaller than the equivalent operation against a normal table (allowing for the array-processing bug on GTTs in 9i).
Regards

Jonathan Lewis

http://www.jlcomp.demon.co.uk/faq/ind_faq.html The Co-operative Oracle Users' FAQ

http://www.jlcomp.demon.co.uk/cbo_book/ind_book.html Cost Based Oracle: Fundamentals

http://www.jlcomp.demon.co.uk/appearances.html Public Appearances - schedule updated 29th Nov 2005

Original Message ----- From: "rjamya" To: "Oracle Discussion List" Sent: Wednesday, January 04, 2006 8:30 PM Subject: Redo question

Is there a way to distinguish between redo generated by activity on GTT Vs non-GTT tables?

Probably a stupid question, but I thought I'd ask anyway.

9204, RAC
rjamya

This space is available for rent.
--

http://www.freelists.org/webpage/oracle-l

--

http://www.freelists.org/webpage/oracle-l Received on Wed Jan 04 2006 - 21:50:35 CST