Andreas Jung wrote at 2006-6-24 09:24 +0200: > ... >One particular app that I have been working on uses very complex queries >with lots of join etc....it would be hard model to implement such queries >on top of the ZODB/ZCatalog.
I disagree with you (partially). The ZODB model (object data stored in a storage with behaviour coded in the clients) is powerful enough to simply implement the relational database data structures: tables and indexes and their corresponding operations. After this implementation, you could perform the same complex queries against the records maintained in these data structures. Of course, this is not the ZCatalog (but a specialized SQL engine) (here I agree with you). The ZCatalog is a search engine targeted at arbitrary unstructured (heterogenous) content but not capable of joins. An SQL engine on the other hand it targeted at highly structured data and forced to use joins (as the relational model even for simple cases force data that belongs together out into different tables). >Another point is performance: this app often >has to perform a lot of insert/update/delete operations within one >transaction (up to 1000 modifications). You would not believe how many objects your "TextIndexNG" modifies when it indexes a single document. Thousands is not very much ;-) -- Dieter _______________________________________________ For more information about ZODB, see the ZODB Wiki: http://www.zope.org/Wikis/ZODB/ ZODB-Dev mailing list - ZODB-Dev@zope.org http://mail.zope.org/mailman/listinfo/zodb-dev