[Zope-dev] Experiments with ORMapping

[Phillip J. Eby]

At 05:42 PM 5/11/01 -0400, Shane Hathaway wrote:
>"Phillip J. Eby" wrote:
>> I'm not quite clear on how exactly you suggest mapping from RDMBS ->
>> ZODB.  There's a *significant* (IMHO) impedance mismatch between ZODB's
>> arbitrarily identified variably structured single records and SQL's
>> content-identified fixed-structure record sets.  This is what application
>> frameworks/toolkits (such as your own DBAPI product) are needed for.
>
>If you implement this at the Storage level, yes, there is a major
>mismatch.  But at the Connection level it makes a lot of sense. 
>Connection basically exposes a pile of pickles as objects; an OR mapping
>exposes a complex schema as objects.
>
>I think that understanding will change the rest of your response. :-)
>

Nope.  As far as I can see, all that does is leverage ZODB Connections as a
crude sort of Rack that only provides a mapping-like interface for
retrieving objects, without helping any of the higher-order needs of an
application.  I guess if you define O-R mapping as "can you store and
retrieve an object's properties from a database", then I guess you've
succeeded at that point.  But if that was all my O-R apps needed, there
would've been no reason to use the RDBMS; I could've just used ZODB and a
BTree with less bother.