DataMapper adapter

[marcoow]

Support for DataMapper would be nice especiall as Rails 3 will make it easy to use DataMapper.

[marcoow]

this is probably hard to do as we cannot (easily) group records by arbitrary strings (e.g. DATE_FORMAT(created_at, 'FORMAT')) in DataMapper.

[kristianmandrup]

I have been working a bit on DataMapper support in my branch of that name. Haven't started with the SQL "heavy" stuff such as grouping yet however...

[marcoow]

Just had a look at your changes. I think ideally we would have it so that the Report classes etc. always are the same for any ORM and we just change the ORM adapter code for them (e.g. by including different modules or something similar). I guess there will be a lot of duplicated code otherwise.

[kristianmandrup]

I'm not so sure. I think the best approach for starters is to implement the DataMapper adapter on its own, trying to mirror the AR API as close as possible. Only then will you be able to determine if it is feasible to create a "generic" mapper with conditional code or metamagic in order to support multiple ORMs.
I'm afraid the "one-suit-fit-all" result will likely be code that is very hard to read, follow and maintain... we will see.