XML Persistence
Abstract
For decades the center of the enterprise was the relational database, everything had to eventually communicate with the database. Many of the technologies even as recently as ten years ago were database centric, EJBs for example. It's fare to say that XML was in it's very earliest stages at the turn of the millennium, it existed but we were still struggling with DTDs. Today it's difficult to imaging an enterprise without some form of XML, most of today's systems, both internal and external send and receive hierarchical messages, usually in XML. Even niche standards like SWIFT are hierarchical in structure. The problem with all this is the impedance mismatch between hierarchical messaging and relational persistence. Object-Relational Matching (ORM) provides a good solution at the simplistic level and solves many problems but is incredibly time consuming and leaves a static binding between the ever-changing message and static relational database as things get more complex. Squeezing hierarchical messages into relational databases with ORM is costly and not maintainable in the long term. This talk explores several ideas for persisting hierarchical data.
