[Zope] Relational queries on zope obj db?

[Jim Penny]

On Mon, May 28, 2001 at 09:56:01PM -0400, Jeff Kowalczyk wrote:
> I'm very interested in using zope, but before I dive in, I have a
> fundamental question that always presents itself when looking at object
> database technologies.
> 
> How does a zope developer select related items across folders from the
> object store? In effect, I'm asking what ZopeDB can do to feign
> relational SQL when it needs a select query on its objects, more
> extensive than a simple knock-out filter.
> 
> The stumbling block is always the same: 
> The problem domain may model perfectly in an ODB's folders/forms, but
> then the customer asks for the kind of report that would be a snap in
> SQL with any relational database, but is very difficult, or horrendously
> slow to do in the object database.
> 
> A simple example would be: customer-class in one folder,
> purchaseorder-class in another, productitem-class in a third; select all
> purchase orders for customerA, displaying each individual productitem
> ordered.
> 
> Thanks! If there's any way to do SQL-like queries against Zope's Object
> Database, or to arrive at the same result, I'm going to check out Zope
> very seriously.

And there is yet a third viewpoint.  Smartobjects lets you delay
choice.  But if you know in advance that you are working with this
kind of problem space, why use machinery to put off the ineveitable.
Zope supports nearly 20 direct interfaces to relational databases 
(depending on how you count multiple interfaces to the same database).
Included are postgresql, mysql, odbc, SAP, solid, oracle, sybase, 
ingres, informix and others.  Working with a mainstream RDBMS should 
simply not be a problem.

Jim Penny
> 
> 
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