[Zope3-Users] Zope3 with RDBMS (avoiding ZODB)?

[David Johnson]

> 1. Is Zope3 already in use in productive environments? Where are  
> they (URLs)?
We are using Zope 3 pretty heavily in a productive environment, but  
unfortunately the URLs are secure at this point.  We build financial  
applications and we are building more.  Our live RDBMS application is  
an administrative tool that queries 4 different financial databases.

> 2. Are there any bigger sites running on Zope3 (> 5 mio. accesses  
> per month)?
We expect to have loads much greater than this when we are completed,  
but we do not have any in production.

>
> 3. Our main problem is: in our Zope2-application we stored our  
> content in a
> RDBMS, we avoided ZODB for that stuff. We are definitely going to  
> use an RDBMS
> (PostgreSQL/MySQL) for the new (Zope3 or Django)-project and still  
> want to avoid
> ZODB where possible. This architectural decision is carved out of  
> stone.
>
> Now, where should we start with it in Zope3 to connect it to an RDBMS?
We do mostly SQL/RDBMS.  We have tried ZAlchmey, and SQLOs, but we  
find them both a bit limiting and simultaneous complex to get them to  
work they way we wanted.  In general when one develops and RDBMS  
application of any size, the database structure can get very  
complex.  In order to integrate them into Zope 3 just right, it's  
best to manually code the containers and objects.  We have been able  
to simplify the process quite a bit and we are very happy with it.   
It's amazing scalable.    If you do decide to go this way, I would be  
glad to share our RBDMS package and procedures.  We've developed some  
guidelines to improve development.  We use MySQL exclusively.

>
> 3.1 We have found 'PostGreSQL Database Adapter' and 'MySQL Database
> Adapter'. Both are from the Isar sprint (2004-11-06). Are they out  
> of date,
> or just 'nearly perfect'? Is anybody using these adapters?
>
We use the MySQL adapter. Zope 3 has a bug in the database adapters  
that requires having to use global utilities (etc/overrides.zcml). It  
is otherwise stable.  In otherwords you cannot currently add and use  
database adapters in Zope 3 through the ZMI but can through  
overrides.zcml.

> 3.2 sqlos - SQLObject Support package (http://codespeak.net/z3/ 
> sqlos/):
> Is it stable? Has someone experiences with it?
> In http://mail.zope.org/pipermail/zope3-users/2006-January/001797.html
> Stephan Richter says: "On the other hand, not many people use  
> sqlos, so
> it might not be as supported as you wish it would be." Is that  
> still right?
>
> 3.3 Also there is 'zsqlmap: Zope3 wrapper for SQLObject'
> (http://www.zope.org/Members/garanin/zsqlmap). This is not really a
> solution for us because the version number is 0.01b and the author  
> says:
> 'NOTE: i tested only postgres.' Not really a capable product...
I find it easier to hand code than use the third party packages. We  
have created our own classes that we find a bit more simple and  
versatile. I suppose this is a preference thing.


> 4. Has anybody practical experience and hints with Zope3 and RDBMS?
>
> 5. The ZMI: In Zope2 we never used it.
> Do we need the ZMI in Zope 3 just if we will not use the ZODB for  
> storing our
> content objects but an RDBMS instead. According to 'Web Component  
> Development
> with Zope 3' by Philipp von Weiterhausen the ZMI is used to manage  
> content objects
> stored in the ZODB, so our assumption is, if we do not store them  
> in the ZODB,
> we do not need the ZMI. Is that right or do we need the ZMI for  
> anything else?
> Do we need ZMI in Zope3 for administration or can we do that with  
> scripts etc.?
The ZMI is everything in regards to management.  The new approach is  
to skin the ZMI to match your own design scheme.  The staff who uses  
our old management applications in UNIX and PHP loves the new Zope 3  
stuff we've done.  It's so simple that we plan on extending some of  
the administrative functionality to our clients.

>
> 6. Last but not least two quotes from the zope3-dev mailinglist
> (http://mail.zope.org/pipermail/zope3-dev/2006-February/018217.html):
>> >Shane Hathaway wrote:
>>> >> It could
>>> >> turn out that people who don't want ZODB really shouldn't use  
>>> Zope at
>>> >> all.
>> >This has been the case in my experience...
>> >Chris Withers
I disagree completely. We use SQL although I do wish that SQL  
integration was stronger.  The structure of Zope is excellent for  
scalability.  You'll pay up front a little, but the simplicity and  
versatility is really great.  We've basically only found 2 platforms  
that scaled well, J2EE and Zope 3.  Zope 3 is vastly better in nearly  
every way in my opinion, except perhaps documentation.  The  
documentation is very weak, but it is a young platform.  The content  
view model of Zope 3 and the clean API's is wonderful.  The platform  
as a whole allows us to develop clean stable scalable code.

--
David