-----Original Message----- From: Alwyn Schoeman [mailto:alwyns@prism.co.za] Sent: Tuesday, December 07, 1999 3:31 AM To: zope@zope.org Subject: [Zope] Databases and zope

Hi,

Do most of the Zope products use the ZODB as a database?

Most, yes. Some products are specifically engineered to use realtional databses in some useful way (like SQLSessions).

If so why?

that's the architecture most choose. Object databases are better at representing structures of heterogenous objects. You can go either way, take squishdot for example, to represent the heirarchical layout of the messages, you would need to store that structure in additional rows/tables. With ZODB, the realtionship between objects is stored along with the objects.

and how easy is it to use say Postgres or MySQL instead of ZODB for Squishdot e.g.?

The application has to be specificly engineered to use ZSQL Methods. Note that ZClass classes can have ZSQL methods as class methods. -Michel