POOP / Python (Object Oriented Persistence) ?

[fermigier]

In article <bln1juwtua.fsf at bitdiddle.concentric.net>,
Jeremy Hylton  <jeremy at beopen.com> wrote:
>fermigier at localhost.localdomain (fermigier) writes:
>
>> I've just read this announcement in Linux Weekly News today:
>> 
>> ``The Poop on persistence (PerlNews). Perl News talks about two new
>> mailing lists for Perl Object Oriented Persistence (Poop). This is an
>> effort to encourage communication between module authors and to address
>> redundant object persistence issues.  Also read about the latest Perl
>> modules.'' (Ref: http://news.perl.org/).
>> 
>> Is there an opportunity to start such a discussion, or at least to gather
>> the solutions that have been developped for Python (and compare them to
>> their Perl/Java counterparts) ?
>
>The two Python solutions that come to mind are the pickle and cPickle
>modules, which just allow you to save and restore Python objects, and
>ZODB, a full-fledged object database from Digital Creations:
>
>http://www.python.org/workshops/2000-01/proceedings/papers/fulton/zodb3.html
>http://www.python.org/workshops/2000-01/proceedings/papers/fulton/fulton-zodb3.pdf
>
>If you are willing to compare these with Perl or Java approaches, I'd
>be interested to hear what you think.

Perl: 
-----

I'm really not much of a perl-head, so I don't have a clue about what's
going on in the perl community. The only project I know so far is Tangram:

http://tangram-persistence.org/
http://www.webtechniques.com/archives/2000/03/jepson/

Java: 
-----

I'm thinking about Jora, the Java Object Relational Adapter
(http://www.ispras.ru/~knizhnik/) and Castor (http://castor.exolab.org/).
Castor is a very nice and complete product, it seems from the feature list:

   * Castor XML: Java object to XML document
   * Castor JDO: Java object persistence to RDBMS
   * Castor DAX: Java object persistence to LDAP
   * Castor DSML: LDAP directory exchange through XML
   * XML-based mapping file specify the mapping between one model and
   another
   * Support for schema-less Java to XML binding
   * In memory caching and write-at-commit reduces JDBC operations
   * Two phase commit transactions, object rollback and deadlock
   detection
   * OQL query mapping to SQL queries
   * EJB container managed persistence provider for OpenEJB

These are the two free software projects I know of, I guess there are
hundreds of commercial projects as well.
   
Python: 
-------

- The Zike project (zike.sourceforge.org) has the ZDC: ``The Zike Data
Classes provide high-level objects for dealing with records in relational
databases. Built on top of the Python DB-API 2.0.''

- There was Joel Shprentz's ``Persistent Storage of Python Objects in
Relational Databases'':

http://www.python.org/workshops/1997-10/proceedings/shprentz.html
http://starship.python.net/crew/shprentz/1997.html

I have seen other products/projects but i can't remember them at the
present.

	S.

-- 
Stéfane Fermigier, <www.fermigier.com>