Quote Originally Posted by hantu
I guess the topic to start would be the format of the metadata. We'd need a DTD or XMLSchema to define how the mapping will be described and furthermore a parser for it. And a strategy to cache the metadata (we don't want to parse the XML-File on every request).
It's a bit too early for this as it would evolve with teh project. For example I doubt inheritance would be implemented at the early stages (if at all) and there are several ways to do it. IT would take a crystal ball to have any idea what would be needed from the metadata. Beware the BDUF demon (big dedsign up front).

As for caching it, there is actually no point. By code generating the data mappers all of the information is converted to code anyway. You will need a generation step anyway to generate the schema scripts, so why not do as much processing as possible at that time ("currying"). Most of the example code posted on Sitepoint so far has used this process.

yours, Marcus