Re: Bookish query Regarding Redo Log

arijitchatterjee123_at_yahoo.co.in (Arijit Chatterjee) wrote in message news:<ea01504d.0411042055.291dcd47_at_posting.google.com>...
> Scenario
> ---------------------------------------------------
> Instance X useing thread 1, which contains two groups
> of online redo log files (groups 1, 2). Thread
> 1 is multiplexed, that is, each group has two copies
> (members) of the redo log files.
>
> So as per above definition when group 1 is filled up
> then LGWR start to write on group 2.But after filling
> up Group 2 it again swiches to Group 1.
>
> Now I have a doubt on this point..
> 1.Does it over write the existing contain of Redo log
> files.
> 2.If yes then how to identify that LGWR is now end of
> present Redo Log.If I need to archive the next Redo
> Log file do that..

Hi, Arijit,

LGWR does overwrite the previous redo log entries when it reuses a log group. To find out where it writes now in the current logfile, look at x$kcccp. See the query by K Gopalakrishnan at http://www.jlcomp.demon.co.uk/faq/redologuse.html. Of course you can simply setup auto archiving.

Yong Huang Received on Fri Nov 05 2004 - 08:15:40 CST