[Zope] newbie: why external database?

Tim Cook tim@freepm.org
Fri, 06 Jul 2001 00:59:41 -0500


Chris Withers wrote:
> 
> > I want to develope a forum with zope. There are products wich store
> > messages and replies in the ZODB. In case this forum will become
> > crowded, this seems to me not the right way ( ? ). I've read that ZODB
> > does a good job if 99% of the users only read.
> 
> Mostly rubbish, try Squishdot:
> http://www.squishdot.org
> 
> I know of people with 2000-6000 postings and no problems.
> 
> > Is this right? Can
> > somebody tell me at wich "size" (e.g. amount of users, hits, etc... ) an
> > external db is needed?
> 
> ...hardly ever, IMNSHO.

I agree with Chris.  I have done testing with tens of thousands
of objects and the only time I see performance hits is with the
management interface (the tree code I believe).  If you have a
custome interface that doesn't have to resolve all those objects
at one time there is no problem.

AFAIK the references to 'many writes vs. reads' applies on a per
object basis.  In an application like Squishdot or FreePM where a
particular object is seldom if ever changed there is no problem. 
The issue regarding the number of writes is caused by the undo
feature.  You create a new copy of the object when you edit it. 
When used for the correct application, the ZODB is very robust.

Cheers,
-- 
Tim Cook, President - Free Practice Management, Inc. 
http://www.FreePM.com Office: (731) 884-4126
ONLINE DEMO: http://www.freepm.org:8080/FreePM