Date: Mon, 13 Jun 2005 17:52:51 -0400
From: postgres@jal.org
To: pgsql-sql@postgresql.org
Subject: Re: Aggregate Functions Template
Message-ID: <20050613215251.GA5713@clueinc.net>
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Hi, Sqlers -

I just installed 8.0.3, and am getting up to speed with the new
features.  First on my list is Tablespaces. In the docs, I see this:


	Note:  There is usually not much point in making more than one
	tablespace per logical file system, since you cannot control the
	location of individual files within a logical file system. However,
	PostgreSQL does not enforce any such limitation, and indeed it is
	not directly aware of the file system boundaries on your system. It
	just stores files in the directories you tell it to use. 

(http://www.postgresql.org/docs/8.0/interactive/manage-ag-tablespaces.html)

I assume this is from the perspective of performance, correct? I was
planning on doing a tablespace per logical project, as we internally
structure most other things that way, and also to ease moving things
around in the event we restructure filesystems, move things between
servers, etc.

In general, at least on our development machines, I was planning on
using them to make data management easier.  I note that I'm not seeing
any Oracle style alter tablespace ... commands for moving things around,
but it appears from that page that it is possible to do by changing the
$PGDATA/pg_tblspc/$symlink and updating pg_tablespace (even if doing so
is 'not recommended'). 

Is this a flawed use of tablespaces?

Thanks,

-j


-- 
Jamie Lawrence                                        jal@jal.org
"Reality must take precedence over public relations, for nature cannot be
fooled."
   - Richard P. Feynman