This post originated from an RSS feed registered with Ruby Buzz by David Heinemeier Hansson. Original Post: No tightly coupling with DBMs in Active Record Feed Title: Loud Thinking Feed URL: http://feeds.feedburner.com/LoudThinking Feed Description: All about the full-stack, web-framework Rails for Ruby and on putting it to good effect with Basecamp Latest Ruby Buzz Posts Latest Ruby Buzz Posts by David Heinemeier Hansson Latest Posts From Loud Thinking

Hi Matt. Thanks for the kind words. I'm honored. I'd just like to correct one misconception about Rails.

When you write "something like Rails would never fly in Java because it appears to be tightly coupled to the database" that's not really true. Active Record (the ORM part of Rails) has a database abstraction layer embedded called Abstract Adapter, which all the specific adapters are implementing transparently.

Hence, your Rails application is not tightly coupled to a specific database, but rather to the Abstract Adapter interface. Since concrete adapters are just ~100 lines of code, it's pretty easy to implement your own adapter if the current offering isn't sufficient.

The PostgreSQL and SQLite adapters were implemented one the same day by one person (Luke Holden). There's a Microsoft SQL Server adapter just around the corner (by Joey Gibson) and I've heard of people working on Oracle and DB2 adapters too.

So the only tightly coupling going on is if you write database-specific SQL. On that account, I'm actually very sympathetic to Jeremy Zawodny's Database Abstraction Layers Must Die!. Chasing database abstraction without a specific business case asking for it is just something You're Not Gonna Need and it's certainly not doing The Simplest Thing Possible.