Re: Exporting through a pipe to Compress

In article <aVLysB1w165w_at_iowegia.uucp>, bob_at_iowegia.uucp (Bob Powers) writes:
|> About 1-2 months ago some posted a message telling how to export
|> through a named pipe into compress to compress the export on the
|> fly. I have lost that copy and would appreciate it if anyone
|> having a copy or the original poster to send me a copy.
|>
|> Bob Powers
|> bob_at_ia-ngnet.army.mil
Here is the answer from Jean Anderson:

Many of my sites do nightly full database exports out of cron. We accept a 24 hour "worst case" data loss. This is not as bad as it might seem. If "the worst" happens (which it has), we rebuild from the previous night's export and re-process, catching up to real-time in a matter of hours.

Back in April, I posted the instructions somebody sent me on compressing UNIX exports. I have been running them since May and it has been great, reliable, reducing the amount of disk we previously had to allocate for exports. I have even had the misfortune of needing to restore from a compressed backup and it worked.

Here are the instructions again. The credit goes to somebody who wishes to remain anonymous because of the employer's restrictions on posting.

    I have found that the best way to do this is using Unix's named-pipes     feature. Simply:

    % mknod /tmp/compresspipe p
    % compress -c </tmp/compresspipe>/backup/oraexp/exp1MAY92.dmp &
    % exp system/manager full=y ..... file=/tmp/compresspipe

    Voila! After the compress receives an EOF (sent by exp), it     terminates, leaving a nice compressed file. This saves using various     undocumented features (as file=stdout must be?!)

    To import, do the same thing:

    % uncompress -c </backup/oraexp/exp1MAY92.dmp >/tmp/compresspipe &     % imp system/manager .... file=/tmp/compresspipe         

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