[Zope3-Users] Re: Newbie relationship question

[Carlo Cardelli]

Stephan Richter wrote:
> On Thursday 27 July 2006 05:17, Carlo Cardelli wrote:
> 
>>- how do I get all my Customers instances? The Customer class is marked
>>as 'Persistent' and 'IContentType'.
> 
> 
> You have several choices:
> 
> 1. Register your customer object as a utility and then do utility lookups. In 
> this case you can reuse code in zope.app.component.vocabulary.
> 2. You probably have a convention where to find customers, like a 
> "CustomerContainer". You can setup your application to easily look up this 
> container to get the entries.

Thank you for your answer. In the meantime I made some progress with 
containers.
In your opinion, which of these 2 options suits best for a large number 
of objects (say, about 100,000 customers)?
About vocabularies: In another post you say you'd rather use them 
instead of sources. As far as I can see, queryable sources seem the main 
choice for management of large collections. Example: a user wants to 
browse a list of all Customers beginning with "a"; I cannot fill the 
HTML page with about 5000 entries, but have to manage "chunks" of 
objects in some way. Hence a queryable object is needed.
Am I wrong? Is there a way to tweak vocabularies to support such cases?
Could anyone provide an example of a similar implementation? Note that I 
have to use a Relational db, so if I understand well I cannot use 
catalogs or similar.

> 
>>A somewhat derived question:
>>- Given a certain Invoice, how do I use the 'reference' to the Customer
>>Object to access the Customer of the Invoice?
> 
> 

Re-reading this now, this was really a silly question...

Thank you again.

Carlo Cardelli.