Re: Smartest way to create test databases (including upgrade) ?

Actually, it's not the export that needs to be "assigned" an adequate sized rb segment. Running a consistent export on an instance that is undergoing DML will cause export to go to the rollback segments to get consistent data, yes, but the export may require the use of any number of segments depending on where the target undo blocks are located.

You want to make sure that any DML during the export remains in the rollback segment(s) as long as possible. Do this by having segments large enough to span all ( or a gread deal of ) DML transactions that will occur during the export.

Hth

-Kevin

"Christian Svensson" <chse30_at_hotmail.com> wrote in message news:ccc2a7eb.0112050912.835c388_at_posting.google.com...
> > > full consistent database export. If I use the consistent=y parameter,
> > > then during the whole export operation no user can change any data.
> >
> > Not true! CONSISTENT=Y just means that the export will be consistent --
the
> > only "gotcha" is that the export will need to be assigned to a rollback
> > segment & if there is a lot of DML going on during the export it may
fail if
> > the rb segment is too small. Just pick a "quiet time" & use DIRECT=Y
(if
> > all character sets are the same) to speed things up.
>
> OK, hmmm, but what I have seen there are no way to assign a specific
> rollback segment for the export operation. I suppose I have to put all
> the other rollback segment offline and then create one big rollback
> segment, so that when the export runs, it can only choose this one. Or
> are there other ways ?
>
> > >
> > > For the IFS testdatabase I suppose I can use the hot backup datafiles
> > > and roll forward with the archived redo logfiles. I know that I must
> > > have the same filedirectory structure for the testdatabase. Since the
> >
> > No -- you can use an edited copy of a TRACE backup controlfile to change
the
> > pathnames by recreating the control file -- you can also change the DB
name
> > that way & the archive log mode. Just get into server manager after
you've
> > copied the files to your test platform, do a "STARTUP NOMOUNT" & execute
an
> > edited version of the file created when you did an "ALTER DATABASE
BACKUP
> > CONTROLFILE TO TRACE". Send me email if you'd like a sample copy of one
of
> > these scripts.
>
> Hmmmmm, but must I not first do a recover ? I mean if I do a startup
> nomount and create a new controlfile, how does Oracle know how many
> archive log it have to roll forward ? Remember that it is database
> files from a hot backup that I use. Not a cold one, but if so, then I
> suppose your way should work. Or am I wrong here ? (Maybe I should
> make an export here also, but it is 17 Gb of data, and it would be
> much better if I could use the hot backup datafiles + redo instead)
>
> Thanks for any clarification about this.
>
> /Christian
Received on Wed Dec 05 2001 - 11:47:33 CST