Message-ID: <447DB844.6010507@pse-consulting.de>
Date: Wed, 31 May 2006 17:37:40 +0200
From: Andreas Pflug <pgadmin@pse-consulting.de>
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To: Tom Lane <tgl@sss.pgh.pa.us>
CC: pgsql-hackers@postgreSQL.org
Subject: Re: Possible TODO item: copy to/from pipe
References: <12436.1149087794@sss.pgh.pa.us>
In-Reply-To: <12436.1149087794@sss.pgh.pa.us>
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Tom Lane wrote:
> After re-reading what I just wrote to Andreas about how compression of
> COPY data would be better done outside the backend than inside, it
> struck me that we are missing a feature that's fairly common in Unix
> programs.  Perhaps COPY ought to have the ability to pipe its output
> to a shell command, or read input from a shell command.  Maybe something
> like
> 
> 	COPY mytable TO '| gzip >/home/tgl/mytable.dump.gz';


> 
> (I'm not wedded to the above syntax, it's just an off-the-cuff thought.)
> 
> Of course psql would need the same capability, since the server-side
> copy would still be restricted to superusers.

Won't help too much, until gzip's output is piped back too, so a 
replacement for COPY .. TO STDOUT COMPRESSED  would be
COPY ... TO '| /bin/gzip |' STDOUT, to enable clients to receive the 
reduced stuff. But clients should be agnostic of server side installed 
tools, and probably not be able to address them directly. Sounds like a 
potential security issue.

Regards,
Andreas