Re: tablespaces in 7.5?

Quoting Brian Maguire <bmaguire(at)vantage(dot)com>:

> That's right it's a big one from a performance and admin perspective. DB2,
> Oracle and Informix have tablespaces. It appears that it has been in the
> postgres crosshair for a few years now. I'm not sure how much has been
> completed so far.
>
>
>
> Few scenarios where they are really important:
>
> 1.
> Right now a database can be as fast as one disk. Tablespaces allow you to
> distribute database objects across multiple physical locations. A big index
> or table can live on separate disks distributing the io activity.
>
> 2.
> Say you are close to running out of disk space and want to grow some of the
> data onto another disk. Table spaces allow you to alter the table space and
> more easily move the big table or indexes onto a different disk rather than
> just moving the entire db to a bigger single disk.
>
> 3.
> Say there is a part of a database that you want to backup every hour, but
> backing up entire database is overkill. You can set it up so it backs up
> different table spaces at different times.
>
> 4.
> Couple other features of tablespaces are that they allow you to allocate
> space to a specific tablespace and to take only part of a database offline or
> online very easily.
>
>
>
> More detail on what they are how to mange them with oracle...
> http://www.engin.umich.edu/caen/wls/software/oracle/server.901/a88856/c04space.htm
>
> http://www.siue.edu/~dbock/cmis565/ch8-tablespaces.htm
> http://www-rohan.sdsu.edu/doc/oracle/server803/A54641_01/ch8.htm
>
>
> -----Original Message-----
> From: John Sidney-Woollett [mailto:johnsw(at)wardbrook(dot)com]
> Sent: Sat 12/13/2003 4:38 AM
> To: Keith C. Perry
> Cc: Bruce Momjian; Brian Maguire; pgsql-general(at)postgresql(dot)org
> Subject: Re: [GENERAL] tablespaces in 7.5?
>
>
>
> My (limited) understanding is that it will give you the ability to:
>
> i) decide what data resides in what tablespace, (database, schema,
> indexes, data [coarser -> finer grain]).
> ii) where the tablespace data is physically located, allowing you to
> distribute your database across disks, or disk arrays.
>
> John Sidney-Woollett
>
> Keith C. Perry said:
> > Quoting Bruce Momjian <pgman(at)candle(dot)pha(dot)pa(dot)us>:
> >
> >> Brian Maguire wrote:
> >> > I am curious if tablespaces are going to be seriously targeted
> >> > for the next version. It really opens up new levels of scalability
> >> > and is a killer feature from an administration perspective.
> >>
> >> I hope so!
> >>
> >> --
> >> Bruce Momjian | http://candle.pha.pa.us
> >> pgman(at)candle(dot)pha(dot)pa(dot)us | (610) 359-1001
> >> + If your life is a hard drive, | 13 Roberts Road
> >> + Christ can be your backup. | Newtown Square, Pennsylvania
> >> 19073
> >>
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> >
> > Excuse my ignorance but what will namespaces give us? I though PG schema
>
> > provided the namespace functionality- 'least the way I am understanding
> > the term.
> >
> > --
> > Keith C. Perry, MS E.E.
> > Director of Networks & Applications
> > VCSN, Inc.
> > http://vcsn.com
> >
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Ok, thats for the response. I take it a PG namespace = Oracle table space (or
namespace is simply the generic term). I can see some definite benefits
especially with disk i/o throughput though I thought database partitioning (I
think that is what its called) would provide the same thing.

This actually sounds like system that might fit well on a Plan 9 OS.

Anyway, thanks to all for the explanations.

--
Keith C. Perry, MS E.E.
Director of Networks & Applications
VCSN, Inc.
http://vcsn.com

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