title: Why do O/R Mappers seem to be the favored persistence approach for DDD users?
body: <p>Why aren't there many DDD stories that use newer nosql tools such as db4o and Cassandra for persistence.  </p>
  
  <p>In my view, the effort involved in O/R mapping seems too high for the returned value.  Being able to report right off the database is the main advantage I can see for my projects.   </p>
  
  <p>On the other hand, db4o seems to almost <strong>be</strong> the Repository pattern and Cassandra's concept of Column Families and SuperColumns seems to be perfect for defining Aggregates and their value objects  (the scalability would just be an added bonus).  Yet, most of the online resources giving examples of DDD projects seem to always default to using [N]Hibernate.</p>
  
  <p>I don't have enough time/resources to take big risks by trying these newer tools on my projects which makes me want to opt for a very well documented approach to persistence.  Is it possible that O/R mapping remains the norm just because people are afraid to give up the oh so reliable SQL?  Should I make the leap?</p>