On Fri, Mar 26, 2010 at 8:34 AM, Rami Ojares <[email protected]> wrote: > Hi, > > I only now stumbled onto JackRabbit project. > And a basic question about it rose in me spontaneously. > > Early in the seventies Ted Codd published relational model as an improvement > over the hierarchical model that had been used for data storage until then. > > So why do we still need a hierarchical model for data storage? >
Some data is more suited to hierarchical data. I'm no expert, but I am a senior Java engineer and I had plenty of database theory classes. JCR just exposes a persistence layer at a level that reflects a object based, hierarchical view of data, which meshes well with current application usages. > Features mentioned like full text search, versioning, transactions, > observation, and more > can be just as well implemented with the relational model. > Sure. And, in many cases Jackrabbit is using a relational db underneath the hood. I consider the JCR as simply a higher level data persistence. > And what does unstructured data mean? RDMBS development is also unstructured. But typically you have to redefined DDL and rebuild the DB each time you modify the structure. Again, JCR provides a higher level persistence layer that gives benefits to application during their "fluid" data structure period, and this period can frequently be lengthier than development schedules would like to portray. > It sounds to me like random noise. > > - rami >
