Re: what is the different?

"Niall Litchfield" <n-litchfield_at_audit-commission.gov.uk> wrote in message news:3b14cc6f$0$12250$ed9e5944_at_reading.news.pipex.net...
> Indeed but I wasn't counting this as a 'usual' operation, just a regular
> one. Methinks I was less than clear. As you say archive log current is
 best
> used as part of backup and recovery, there may be other reasons why a dba
> wishes to issue switch logfile - however they probably aren't either usual
> or regular.

Well.... Have to say that, for performance reasons, I'd be implementing huge online redo logs that never switch of their own accord, and scheduling an 'alter system switch logfile' at 1.00am. I'd rather not have checkpoints occuring throughout the day and slowing things down, and this way I can control when the checkpoints take place.

Issuing it every morning sounds fairly usual and regular to me! ;-)

Regards
HJR
>Sorry for the wooly thinking and turn of phrase.
>
>
> --
> Niall Litchfield
> Oracle DBA
> Audit Commission UK
> "Spencer" <spencerp_at_swbell.net> wrote in message
> news:P0eQ6.438$My3.106492_at_nnrp3.sbc.net...
> > in our hot backup scripts, we use the "archive log current" syntax to
> > ensure that the current log file is archived. prior to the introduction
> > of this syntax, the script used the "switch logfile", and then waited
 for
> > several minutes to give ARCH enough time to archive the log file,
> > before continuing.
> >
> > one place we use the the
> > "Niall Litchfield" <niall.litchfield_at_dial.pipex.com> wrote in message
> > news:3b114c75$0$15030$cc9e4d1f_at_news.dial.pipex.com...
> > > alter system switch logfile switches between current online redo logs.
 It
> > > (should) always work.
> > >
> > > alter system archive log current will archive the (current) redo log.
 It
> > > thus requires all of the prerequisites for archiving redo logs.
> > >
> > > Most likely causes for the second command to fail
> > >
> > > 1. you are not in archivelog mode
> > > 2. you have run out of space in your archive log destination.
> > >
> > > The error message in the alert log will tell you what the problem is.
> > >
> > > IMO you should also not usually need to issue the second command since
> > > oracle will quite happily archive redo logs for you automatically.
> > >
> > >
> > > --
> > >
> > > Niall Litchfield
> > > Oracle DBA
> > > Audit Commission UK
> > > "Cheong" <leslie_hk_at_hotmail.com> wrote in message
> > > news:3b113326_at_newsgate.imsbiz.com...
> > > > Can anyone tell me what is the different of the following two
 commands
> > > >
> > > > alter system archive log current
> > > > alter system switch logfile
> > > >
> > > > and why the first command always produce and error a message fail to
 arhive
> > > > log ... in alert log file.
> > > >
> > > > Thanks in advance
> > > >
> > > > Antony
> > > >
> > > >
> > >
> > >
> > >
> >
> >
>
>
Received on Wed May 30 2001 - 07:50:43 CDT