Skip site navigation (1) Skip section navigation (2)

Re: Databases Vs. Schemas

From: Adam Ruth <adamruth(at)mac(dot)com>
To: "Subbiah, Stalin" <SSubbiah(at)netopia(dot)com>
Cc: "'pgsql-admin(at)postgresql(dot)org'" <pgsql-admin(at)postgresql(dot)org>,"'pgsql-performance(at)postgresql(dot)org'" <pgsql-performance(at)postgresql(dot)org>
Subject: Re: Databases Vs. Schemas
Date: 2004-03-24 03:31:46
Message-ID: C75DB9B7-7D43-11D8-A4B4-000A959D1424@mac.com (view raw or flat)
Thread:
Lists: pgsql-adminpgsql-performance
On Mar 23, 2004, at 11:16 AM, Subbiah, Stalin wrote:

>> And we also created rules to allow update, delete, and insert on those
>> views so that they looked like tables.  The reason we did this is
>> because we ran into issues with too many open files during pg_dump 
>> when
>> we had thousands of tables instead of about 1 hundred tables and
>> thousands of views.
>
> Is it because you had smaller value set for max. allowable number of 
> open
> files descriptor. what was ulimit -a set to ?

It was actually running on OS X and it was a shared memory issue.  We 
would have had to recompile the Darwin kernel to get a bigger SHMMAX, 
but this solution seemed better since we would possibly be installing 
on servers where we wouldn't have that much leeway.  I think that the 
view idea works better for a number of other reasons.  For one, I can 
do a query on the base table and see all of the rows for all of the 
schemas at once, that has proven quite useful.

>
>> We, however, did have a need to periodically select data from 2 
>> schemas
>> at a time, and it was simpler logic than if we needed 2 database
>> connections.
>
> Adam Ruth
>
> On Mar 22, 2004, at 2:30 PM, Subbiah, Stalin wrote:
>
>> --sorry to repost, just subscribed to the list. hopefully it gets to
>> the
>> list this time --
>>
>> Hi All,
>>
>> We are evaluating the options for having multiple databases vs.
>> schemas on a
>> single database cluster for a custom grown app that we developed. Each
>> app
>> installs same set of tables for each service. And the service could
>> easily
>> be in thousands. so Is it better to have 1000 databases vs 1000
>> schemas in a
>> database cluster. What are the performance overhead of having multiple
>> databases vs. schemas (if any). I'm leaning towards having schemas
>> rather
>> than databases but i would like to get others opinion on this.
>> Appreciate
>> your reply.
>>
>> Thanks,
>> Stalin
>>
>> ---------------------------(end of
>> broadcast)---------------------------
>> TIP 3: if posting/reading through Usenet, please send an appropriate
>>       subscribe-nomail command to majordomo(at)postgresql(dot)org so that 
>> your
>>       message can get through to the mailing list cleanly
>>
>


In response to

pgsql-performance by date

Next:From: Greg StarkDate: 2004-03-24 03:42:20
Subject: Re: SLOW query with aggregates
Previous:From: mattDate: 2004-03-23 23:35:47
Subject: Re: [ADMIN] Benchmarking postgres on Solaris/Linux

pgsql-admin by date

Next:From: Mark KirkwoodDate: 2004-03-24 08:53:31
Subject: Re: [PERFORM] Benchmarking postgres on Solaris/Linux
Previous:From: Bruce MomjianDate: 2004-03-24 00:50:24
Subject: Re: [Retrieved]RE: backup and recovery

Privacy Policy | About PostgreSQL
Copyright © 1996-2014 The PostgreSQL Global Development Group