[Zope] RE: URGENT: Can't start up zope

[Brian Lloyd]

> > On an abstract level, the statement "if Zope data can be accessed by
> > other applications" seems to be a pretty clear violation of
> > encapsulation, but that's just the object zealot party line. :^)
> 
> Allowing the IT guys to write ad-hoc reports against the data 
> in the ZODB may be
> a showstopping requirement in some projects;  integration 
> with existing
> reporting tools would necessitate access via SQL.

I'd like to play devil's advocate here for a moment - can you 
give me an example of an application where ad-hoc reports on
_Zope_ object data are a requirement? Why would you not use Zope's
relational database integration tools (SQL Methods, etc.), to
deal with this kind of enterprise data? That way any existing
ad-hoc reporting tools that work with your RDBMS could be used.


> We could view such requirements as a clarion call for another layer of
> (refactored) design:  perhaps providing hooks to allow the 
> Zope developer to
> tackle the OO<-->RDBMS mapping problem head on would be 
> useful?  I see these
> hooks as similar to SQL adapters, but in the service of 
> persistence, rather than
> method invocation.  

The real point of supporting an abstract data storage in Z2 is to 
let folks use a backing store that they feel comfortable with (as 
far as stability support, scalability, availability, etc.), rather
than to try to integrate Zope into the relational (or even object/
relational) world. I'm a bit curious what those hooks would look
like - I suspect that the more you think about them, the more there
will need to be :^) 


> Breaking the dependency on pickling, 
> using instead, say, XML
> stored as a blob, might be helpful in some circumstances, as well.

Is XML stored in RDB tables that much better than pickles? Are 
there (reporting, etc.) tools that support this, or is it just
that XML would be slightly more human-readable? Note that I'm
not necessarily against such a thing, I'm just curious what 
purpose it serves.


Brian Lloyd        brian@digicool.com
Software Engineer  540.371.6909              
Digital Creations  http://www.digicool.com