From: Kirk Haines <khaines@...>
Date: 2004-08-24T13:10:20+09:00
Subject: Re: Object-Relational Mapping

On Tue, 24 Aug 2004 08:59:44 +0900, Pablo Lorenzzoni wrote

> Here is the list of those I know of:
> * Active_Record - http://activerecord.rubyonrails.org/
> * Lafcadio - http://lafcadio.rubyforge.org/
> * Highcrest::Persistence - http://highcrest.topcities.com/
> * Vapor - http://vapor.rubyforge.org/
> * Kansas - http://enigo.com/projects/kansas/index.html
> 
> Do any one know any of those above and can suggest me which one is 
> the best
> (and why)? Or maybe point me so some other implementation...

You're going to have to try a few out and see what you like.  There are a lot
of differences in the libraries you list.  Lafcadio and Active Record require
specific adaptors for specific databases, so if there's a database that you
want to use that doesn't have an adaptor, you will have to be the one to write
the adaptor.  AR has a bunch of interest and has several people actively
working on things for it.  It makes some assumptions on table design, but
following them lets it simplify a lot of the mechanics of declaring relationships.

Kansas, which is what I am working on developing, works via DBI, which has
it's own tradeoffs versus dedicated adaptors.  It _should_ work on any db that
works with DBI, given that a few basic things are provided by the DBD driver
(though it appears that the SQLite driver may be a problem; I'm trying to
devise a workaround).  It is not as mature as either AR or Lafcadio, but is
stable and solid enough for me to be using it in software that is getting hit
hard regularly.  It is closer to AR than to Lafcadio in how relationships are
defined, but is a little wordier in defining relationships than AR, a tradeoff
for making fewer assumptions and being more flexible in table design.

Read some of the docs.  Looks at some of the examples, download a few of them
and try them out.  One of them will appeal to you more than the others.  Give
that one a serious try.

If you decide to give Kansas a go, feel free to email me if you run into any
problems.


Kirk Haines