Re: tablespaces in 7.5?

Quoting Brian Maguire <bmaguire@vantage.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@wardbrook.com]
>     Sent: Sat 12/13/2003 4:38 AM
>     To: Keith C. Perry
>     Cc: Bruce Momjian; Brian Maguire; pgsql-general@postgresql.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@candle.pha.pa.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@candle.pha.pa.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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