[Zope] returning related objects

VanL vlindberg@verio.net
Tue, 10 Sep 2002 09:37:39 -0600


Hello,

I have some objects stored in the ZODB that I am accessing via a 
ZCatalog query. The problem is that I sometimes don't want the exact 
results of a search, but an item that is related to it via the ZODB 
tree.  For example, say I have the following hierarchy (everything is a 
folderish object):

Orchards/
    Hill Orchard/
        Manager
        Fields/
            North_Field/
                AppleTypes/
                    McIntosh
                    Golden Delicious
            South_Field/
                AppleTypes/
                    Red Delicious
            East_Field/
                AppleTypes/
                    McIntosh
                    Fuji
   Valley Orchard/
        Manager
        Fields/
            North_Field/
                AppleTypes/
                    Golden Delicious
            South_Field/
                AppleTypes/
                    Granny

I want to do queries like:
"Who are the managers that look over Golden Delicious Fields?"
"What kinds of apples are grown in the Valley Orchard?"

Currently, I am trying to do a zcatalog query for the known item (say, 
the Orchard) and then run up or down the acquisition chain to retrieve 
the unknown, but related quantity.

Is there an easier way to do this?  One of the things that I like about 
Zope is the ability to store objects in their natural hierarchies.  Can 
I use that to get information about objects that are related to my 
current object?

Thanks,

VanL