compressed file. It's compresses the data as it goes and doesn't leave
it till the end.
Parfile INCLUDES...
Parfile INCLUDES...
tim.kears
...@milton-keynes.gov.uk (Tim Kearsley) wrote in message <
news:725736ef.0211120033.43591df2@posting.google.com>...
> tim.kears
...@milton-keynes.gov.uk (Tim Kearsley) wrote in message <
news:725736ef.0211110711.3a8567e4@posting.google.com>...
> > Hi all,
> > Environment here is:
> > Oracle 8i (mostly 8.1.7)
> > AIX 4.3.3
> > RS6000 SP hardware
> > For a long time I've used the technique of exporting databases
> > directly to a compressed file by using a named pipe as the FILE
> > parameter in the export and running a compress command in the
> > background to read whatever comes into the pipe and write out a
> > compressed file. This works very well.
> > The question is this:
> > Will a similar technique work for multiple files? That is, if I want
> > to generate a number of compressed files from the export (in my case
> > to avoid hitting a 2 Gbyte file size limit in a non large file-enabled
> > AIX filesystem) can I specify several named pipes in the FILE
> > parameter for the export and fire off a number of background processes
> > to read from the pipes? I'm not clear how the FILESIZE parameter for
> > the export would be used. Would the export start writing to another
> > pipe once it had written FILESIZE bytes to the previous pipe?
> > I'll experiemnt in the meantime, but would be very interested to know
> > whether anyone has tried this and if they were successful.
> Well I *have* experimented and have a bit more information now. It
> seems you can use multiple named pipes in the FILE parameter for the
> export and if you kick off a similar number of background processes to
> read those pipes and compress what comes in to them then you get a set
> of compressed export dumps.
> For example, in the export parameter file:
> FILE=/tmp/pipe1,/tmp/pipe2,/tmp/pipe3
> Create the pipes with:
> mknod /tmp/pipe1 p
> mknod /tmp/pipe2 p
> mknod /tmp/pipe3 p
> And create background processes to compress what is read into the
> pipe:
> compress < /tmp/pipe1 > exp1.dmp.Z &
> compress < /tmp/pipe2 > exp2.dmp.Z &
> compress < /tmp/pipe3 > exp3.dmp.Z &
> As I'm no Unix expert I wouldn't be at all surprised if there's a more
> elegant way of doing this. If so, I'd love to know!
> Cheers.
> Tim Kearsley
> Database Manager
> Milton Keynes Council