[Zope] Understand ZODB Query?
J Cameron Cooper
Tue, 11 Mar 2003 13:34:57 -0600
> - I can easily perform SQL statement to lookup for some information
> such as, total employee, who are above 30 years old, and who has the
> Lastname of 'Smith'.
> - I can easily retrieve information from multiple tables and combine
> it as data objects.
> But how can I do this in ZODB?
1) If your data set is not too big, you can do it programmatically Python:
set = folder.objectValues()
results = 
for elt in set:
if (elt.age > 30) and (elt.lastname=='Smith'):
One can easily replace '30' and 'Smith' with parameters to get a more
2) Use ZCatalog for this if you have larger sets to avoid unnecessary
But I suspect the larger problem is that you're thinking tabularly.
Trying to make a 1-to-1 translation between an object-storage scheme and
a relational-storage scheme isn't always (or maybe usually) going to
work. I know no magic processes for this, unfortunately.