Re: Poatgresql database on more than one disk

Barry wrote:

> Hi All,
>
> I am a newcommer to Postgresql, currently I am looking at moving
> a Pick based application across to PostgreSQL.
>
> I am using RH Linux and Postgresql 7.3.6
>
> The test system I am using has a 2 channel raid card with a disk pack
> connected to each channel. The OS and Postgresql sits on its own internal
> disk.
>
> I would like to be able to use one disk pack for development and the
> other for end user testing / verification (the tape drive can only backup
> one disk pack completely, not both)
>
> I have spent a fair amount of time researching how I can run two
> databases, one on each disk pack but have not been able to find a
> solution.
>
> Is it possible to configure Postgresql to have seperate databases
> on seperate disks ?

Not easily as will be with the Table Space feature that most probably
will be present on 7.5

With 7.3.6 what you can do is move your db and create a link in the
original place:

-bash-2.05b$ oid2name
All databases:
---------------------------------
17142 = kalman
19185 = photodb
27895 = empdb
1 = template1
17141 = template0
5776262 = logs

-bash-2.05b$ pwd
/var/lib/pgsql/data/base

-bash-2.05b$ ll
total 32
drwx------ 2 postgres postgres 4096 Feb 8 15:18 1
drwx------ 2 postgres postgres 4096 Feb 8 03:56 17141
drwx------ 2 postgres postgres 4096 May 25 19:37 17142
drwx------ 2 postgres postgres 8192 Feb 8 15:58 19185
drwx------ 3 postgres postgres 8192 May 16 02:46 27895
drwx------ 2 postgres postgres 4096 May 18 00:06 5776262

in my case if I want the database kalman to another disk what I have to
do is: stop the engine, move the directory /var/lib/pgsql/data/base/17142
to the new location and create the link.
With the same mechanism you can also place different tables in different
disks.

I hope this help you.

Regards
Gaetano Mendola